D-Tale was born out a conversion from SAS to Python. What was originally a perl script wrapper on top of SAS's insight function is now a lightweight web client on top of Pandas data structures. D-Tale is the combination of a Flask back-end and a React front-end to bring you an easy way to view & analyze Pandas data structures. Currently this tool supports such Pandas objects as DataFrame, Series, MultiIndex, DatetimeIndex & RangeIndex. It integrates seamlessly with ipython notebooks & python/ipython terminals.
- Getting Started
- UI
- For Developers
- Startup Behavior
- Documentation
- Requirements
- Acknowledgements
- License
| PyCharm | jupyter |
|---|---|
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Setup/Activate your environment and install the egg
Python 3
# create a virtualenv, if you haven't already created one
$ python3 -m venv ~/pyenvs/dtale
$ source ~/pyenvs/dtale/bin/activate
# install dtale egg (important to use the "--upgrade" every time you install so it will grab the latest version)
$ pip install --upgrade dtalePython 2
# create a virtualenv, if you haven't already created one
$ python -m virtualenv ~/pyenvs/dtale
$ source ~/pyenvs/dtale/bin/activate
# install dtale egg (important to use the "--upgrade" every time you install so it will grab the latest version)
$ pip install --upgrade dtaleNow you will have to ability to use D-Tale from the command-line or within a python-enabled terminal
This comes courtesy of PyCharm
Feel free to invoke python or ipython directly and use the commands in the screenshot above and it should work
import dtale
import pandas as pd
df = pd.DataFrame([dict(a=1,b=2,c=3)])
# Assigning a reference to a running D-Tale process
d = dtale.show(df)
# Accessing data associated with D-Tale process
tmp = d.data.copy()
tmp['d'] = 4
# Altering data associated with D-Tale process
# FYI: this will clear any front-end settings you have at the time for this process (filter, sorts, formatting)
d.data = tmp
# Shutting down D-Tale process
d.kill()
# using Python's `webbrowser` package it will try and open your server's default browser to this process
d.open_browser()
# There is also some helpful metadata about the process
d._data_id # the process's data identifier
d._url # the url to access the process
d2 = dtale.get_instance(d._data_id) # returns a new reference to the instance running at that data_id
dtale.instances() # returns a dictionary of all instances available, this would be { 1: ... }Within any jupyter (ipython) notebook executing a cell like this will display a small instance of D-Tale in the output cell. Here are some examples:
dtale.show |
assignment | instance |
|---|---|---|
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If you are running ipython<=5.0 then you also have the ability to adjust the size of your output cell for the most recent instance displayed:
One thing of note is that alot of the modal popups you see in the standard browser version will now open separate browser windows for spacial convienence:
| Column Menus | Correlations | Describe | Histogram | Charts | Instances |
|---|---|---|---|---|---|
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Base CLI options (run dtale --help to see all options available)
| Prop | Description |
|---|---|
--host |
the name of the host you would like to use (most likely not needed since socket.gethostname() should figure this out) |
--port |
the port you would like to assign to your D-Tale instance |
--name |
an optional name you can assign to your D-Tale instance (this will be displayed in the <title> & Instances popup) |
--debug |
turn on Flask's "debug" mode for your D-Tale instance |
--no-reaper |
flag to turn off auto-reaping subprocess (kill D-Tale instances after an hour of inactivity), good for long-running displays |
--open-browser |
flag to automatically open up your server's default browser to your D-Tale instance |
--force |
flag to force D-Tale to try an kill any pre-existing process at the port you've specified so it can use it |
Loading data from arctic
dtale --arctic-host mongodb://localhost:27027 --arctic-library jdoe.my_lib --arctic-node my_node --arctic-start 20130101 --arctic-end 20161231Loading data from CSV
dtale --csv-path /home/jdoe/my_csv.csv --csv-parse_dates dateLoading data from a Custom loader
- Using the DTALE_CLI_LOADERS environment variable, specify a path to a location containing some python modules
- Any python module containing the global variables LOADER_KEY & LOADER_PROPS will be picked up as a custom loader
- LOADER_KEY: the key that will be associated with your loader. By default you are given arctic & csv (if you use one of these are your key it will override these)
- LOADER_PROPS: the individual props available to be specified.
- For example, with arctic we have host, library, node, start & end.
- If you leave this property as an empty list your loader will be treated as a flag. For example, instead of using all the arctic properties we would simply specify
--arctic(this wouldn't work well in arctic's case since it depends on all those properties)
- You will also need to specify a function with the following signature
def find_loader(kwargs)which returns a function that returns a dataframe orNone - Here is an example of a custom loader:
from dtale.cli.clickutils import get_loader_options
'''
IMPORTANT!!! This global variable is required for building any customized CLI loader.
When find loaders on startup it will search for any modules containing the global variable LOADER_KEY.
'''
LOADER_KEY = 'testdata'
LOADER_PROPS = ['rows', 'columns']
def test_data(rows, columns):
import pandas as pd
import numpy as np
import random
from past.utils import old_div
from pandas.tseries.offsets import Day
from dtale.utils import dict_merge
import string
now = pd.Timestamp(pd.Timestamp('now').date())
dates = pd.date_range(now - Day(364), now)
num_of_securities = max(old_div(rows, len(dates)), 1) # always have at least one security
securities = [
dict(security_id=100000 + sec_id, int_val=random.randint(1, 100000000000),
str_val=random.choice(string.ascii_letters) * 5)
for sec_id in range(num_of_securities)
]
data = pd.concat([
pd.DataFrame([dict_merge(dict(date=date), sd) for sd in securities])
for date in dates
], ignore_index=True)[['date', 'security_id', 'int_val', 'str_val']]
col_names = ['Col{}'.format(c) for c in range(columns)]
return pd.concat([data, pd.DataFrame(np.random.randn(len(data), columns), columns=col_names)], axis=1)
# IMPORTANT!!! This function is required for building any customized CLI loader.
def find_loader(kwargs):
test_data_opts = get_loader_options(LOADER_KEY, kwargs)
if len([f for f in test_data_opts.values() if f]):
def _testdata_loader():
return test_data(int(test_data_opts.get('rows', 1000500)), int(test_data_opts.get('columns', 96)))
return _testdata_loader
return NoneIn this example we simplying building a dataframe with some dummy data based on dimensions specified on the command-line:
--testdata-rows--testdata-columns
Here's how you would use this loader:
DTALE_CLI_LOADERS=./path_to_loaders bash -c 'dtale --testdata-rows 10 --testdata-columns 5'Once you have kicked off your D-Tale session please copy & paste the link on the last line of output in your browser
The information in the upper right-hand corner gives grid dimensions 
- lower-left => row count
- upper-right => column count
- clicking the triangle displays the menu of standard functions (click outside menu to close it)
- to select a column, simply click on the column header (to deselect, click the column header again)
- You'll notice that the columns you've selected will display in the top of your browser
- You'll notice that the columns you've selected will display in the top of your browser
View all the columns & their data types as well as individual details of each column
| Data Type | Display | Notes |
|---|---|---|
| date |  |
|
| string |  |
If you have less than or equal to 100 unique values they will be displayed at the bottom of your popup |
| int |  |
Anything with standard numeric classifications (min, max, 25%, 50%, 75%) will have a nice boxplot with the mean (if it exists) displayed as an outlier if you look closely. |
| float |  |
Apply a simple pandas query to your data (link to pandas documentation included in popup)
| Editing | Result |
|---|---|
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Build custom charts based off your data.
- To build a chart you must pick a value for X & Y inputs which effectively drive what data is along the X & Y axes
- If your data along the x-axis has duplicates you have three options:
- specify a group, which will create series for each group
- specify an aggregation, you can choose from one of the following: Count, First, Last, Mean, Median, Minimum, MAximum, Standard Deviation, Variance, Mean Absolute Deviation, Product of All Items, Sum, Rolling
- Specifying a "Rolling" aggregation will also require a Window & a Computation (Correlation, Coiunt, Covariance, Kurtosis, Maximum, Mean, Median, Minimum, Skew, Standard Deviation, Sum or Variance)
- specify both a group & an aggregation
- Click the "Load" button which will load the data and display the default cahrt type "line"
- You now have the ability to toggle between different chart types: line, bar, stacked bar, pie & wordcloud
- If you have specified a group then you have the ability between showing all series in one chart and breaking each series out into its own chart "Chart per Group"
Here are some examples with the following inputs: X: date, Y: Col0, Group: security_id, Aggregation: Mean, Query: security_id in (100000, 100001) and date >= '20181220' and date <= '20181231'
| Chart Type | Chart | Chart per Group |
|---|---|---|
| line |  |
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| bar |  |
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| stacked |  |
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| pie |  |
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| wordcloud |  |
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Selecting multiple columns for the Y-Axis will produce similar results to grouping in the sense that the chart will contain multiple series, but the difference is that for each column there will be a different Y-Axis associated with it in case the values contained within each column are on different scales.
| Multi Y-Axis | Editing Axis Ranges |
|---|---|
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With a bar chart that only has a single Y-Axis you have the ability to sort the bars based on the values for the Y-Axis
| Pre-sort | Post-sort |
|---|---|
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This is a very powerful feature with many more features that could be offered (heatmaps, different statistical aggregations, etc...) so please submit issues :)
Shows a pearson correlation matrix of all numeric columns against all other numeric columns
- By deafult, it will show a grid of pearson correlations (filtering available by using drop-down see 2nd table of screenshots)
- If you have a date-type column, you can click an individual cell and see a timeseries of pearson correlations for that column combination
- Currently if you have multiple date-type columns you will have the ability to toggle between them by way of a drop-down
- Furthermore, you can click on individual points in the timeseries to view the scatter plot of the points going into that correlation
| Matrix | Timeseries | Scatter |
|---|---|---|
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| Col1 Filtered | Col2 Filtered | Col1 & Col2 Filtered |
|---|---|---|
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When the data being viewed in D-Tale has date or timestamp columns but for each date/timestamp vlaue there is only one row of data the behavior of the Correlations popup is a little different
- Instead of a timeseries correlation chart the user is given a rolling correlation chart which can have the window (default: 10) altered
- The scatter chart will be created when a user clicks on a point in the rollign correlation chart. The data displayed in the scatter will be for the ranges of dates involved in the rolling correlation for that date.
| Data | Correlations |
|---|---|
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This will hide any non-float columns (with the exception of the index on the right) and apply a color to the background of each cell
- Each float is renormalized to be a value between 0 and 1.0
- Each renormalized value is passed to a color scale of red(0) - yellow(0.5) - green(1.0)
Turn off Heat Map by clicking menu option again
This will give you information about other D-Tale instances are running under your current Python process.
For example, if you ran the following script:
import pandas as pd
import dtale
dtale.show(pd.DataFrame([dict(foo=1, bar=2, biz=3, baz=4, snoopy_D_O_double_gizzle=5)]))
dtale.show(pd.DataFrame([
dict(a=1, b=2, c=3, d=4),
dict(a=2, b=3, c=4, d=5),
dict(a=3, b=4, c=5, d=6),
dict(a=4, b=5, c=6, d=7)
]))
dtale.show(pd.DataFrame([range(6), range(6), range(6), range(6), range(6), range(6)]), name="foo")This will make the Instances button available in all 3 of these D-Tale instances. Clicking that button while in the first instance invoked above will give you this popup:
The grid above contains the following information:
- Process: timestamp when the process was started along with the name (if specified in
dtale.show()) - Rows: number of rows
- Columns: number of columns
- Column Names: comma-separated string of column names (only first 30 characters, hover for full listing)
- Preview: this button is available any of the non-current instances. Clicking this will bring up left-most 5X5 grid information for that instance
- The row highlighted in green signifys the current D-Tale instance
- Any other row can be clicked to switch to that D-Tale instance
Here is an example of clicking the "Preview" button:
This will give you information about what version of D-Tale you're running as well as if its out of date to whats on PyPi.
| Up To Date | Out Of Date |
|---|---|
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Mostly a fail-safe in the event that your columns are no longer lining up. Click this and should fix that
This is only available if you are not viewing D-Tale from an jupyter notebook output cell. This will toggle between the two types of functionality:
- Full-mode: column selection, column-specific options in in the main menu & all tools are displayed in modal windows
- Iframe-mode: no column selection, column-specific menus on head click & some tools will now open separate browser windows (Correlations, Describe, Histogram & Instances)
Pretty self-explanatory, kills your D-Tale session (there is also an auto-kill process that will kill your D-Tale after an hour of inactivity)
Moves your column to the front of the "unlocked" columns
Adds your column to "locked" columns
- "locked" means that if you scroll horizontally these columns will stay pinned to the right-hand side
- this is handy when you want to keep track of which date or security_id you're looking at
- by default, any index columns on the data passed to D-Tale will be locked
Removed column from "locked" columns
Applies/removes sorting (Ascending/Descending/Clear) to the column selected
Important: as you add sorts they sort added will be added to the end of the multi-sort. For example:
| Action | Sort |
|---|---|
| select "a" | |
| sort asc | a (asc) |
| deselect "a" | a (asc) |
| select "b" | a (asc) |
| sort desc | a (asc), b(desc) |
| select "a" | a (asc), b(desc) |
| clear sort | b(desc) |
| sort desc | b(desc), a(desc) |
| select "b" | b(desc), a(desc) |
| clear sort | |
| sort asc | a (asc), b(asc) |
Apply simple formats to numeric values in your grid
| Editing | Result |
|---|---|
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Here's a grid of all the formats available with -123456.789 as input:
| Format | Output |
|---|---|
| Precision (6) | -123456.789000 |
| Thousands Sep | -123,456.789 |
| Abbreviate | -123k |
| Exponent | -1e+5 |
| BPS | -1234567890BPS |
| Red Negatives | -123457 |
Display histograms in any number of bins (defaul: 20), simply type a new integer value in the bins input
These are the same functions as the menu listed earlier, but there is no more column selection (instead theres menus for each column). Also the following buttons will no longer open modals, but separate browser windows: Correlations, Describe & Instances (see images from Jupyter Notebook, also Charts will always open in a separate browser window)
There are also menus associated with each column header which can be trigger by clicking on a column header. The functions that are contained within each are: Sorting, Move To Front, Lock/Unlock, Histogram, Describe, Formats (see image from Jupyter Notebook)
- Histogram & Describe open separate browser windows
Clone the code (git clone ssh://[email protected]:manahl/dtale.git), then start the backend server:
$ git clone ssh://[email protected]:manahl/dtale.git
# install the dependencies
$ python setup.py develop
# start the server
$ python dtale --csv-path /home/jdoe/my_csv.csv --csv-parse_dates dateYou can also run dtale from PyDev directly.
You will also want to import javascript dependencies and build the source:
$ npm install
# 1) a persistent server that serves the latest JS:
$ npm run watch
# 2) or one-off build:
$ npm run buildThe usual npm test command works:
$ npm test
You can run individual test files:
$ TEST=static/__tests__/dtale/DataViewer-base-test.jsx npm run test-file
You can lint all the JS and CSS to confirm there's nothing obviously wrong with it:
$ npm run lint -sYou can also lint individual JS files:
$ npm run lint-js-file -s -- static/dtale/DataViewer.jsxYou can auto-format code as follows:
$ npm run formatYou can build python 27-3 & run D-Tale as follows:
$ yarn run build
$ docker-compose build dtale_2_7
$ docker run -it --network host dtale_2_7:latest
$ python
>>> import pandas as pd
>>> df = pd.DataFrame([dict(a=1,b=2,c=3)])
>>> import dtale
>>> dtale.show(df)Then view your D-Tale instance in your browser using the link that gets printed
You can build python 36-1 & run D-Tale as follows:
$ yarn run build
$ docker-compose build dtale_3_6
$ docker run -it --network host dtale_3_6:latest
$ python
>>> import pandas as pd
>>> df = pd.DataFrame([dict(a=1,b=2,c=3)])
>>> import dtale
>>> dtale.show(df)Then view your D-Tale instance in your browser using the link that gets printed
Here's a little background on how the dtale.show() function works:
- by default it will look for ports between 40000 & 49000, but you can change that range by specifying the environment variables DTALE_MIN_PORT & DTALE_MAX_PORT
- think of sessions as python consoles or jupyter notebooks
- Session 1 executes
dtale.show(df)our state is:
| Session | Port | Active Data IDs | URL(s) |
|---|---|---|---|
| 1 | 40000 | 1 | http://localhost:40000/dtale/main/1 |
- Session 1 executes
dtale.show(df)our state is:
| Session | Port | Active Data IDs | URL(s) |
|---|---|---|---|
| 1 | 40000 | 1,2 | http://localhost:40000/dtale/main/[1,2] |
- Session 2 executes
dtale.show(df)our state is:
| Session | Port | Active Data IDs | URL(s) |
|---|---|---|---|
| 1 | 40000 | 1,2 | http://localhost:40000/dtale/main/[1,2] |
| 2 | 40001 | 1 | http://localhost:40001/dtale/main/1 |
- Session 1 executes
dtale.show(df, port=40001, force=True)our state is:
| Session | Port | Active Data IDs | URL(s) |
|---|---|---|---|
| 1 | 40001 | 1,2,3 | http://localhost:40001/dtale/main/[1,2,3] |
- Session 3 executes
dtale.show(df)our state is:
| Session | Port | Active Data IDs | URL(s) |
|---|---|---|---|
| 1 | 40001 | 1,2,3 | http://localhost:40001/dtale/main/[1,2,3] |
| 3 | 40000 | 1 | http://localhost:40000/dtale/main/1 |
- Session 2 executes
dtale.show(df)our state is:
| Session | Port | Active Data IDs | URL(s) |
|---|---|---|---|
| 1 | 40001 | 1,2,3 | http://localhost:40001/dtale/main/[1,2,3] |
| 3 | 40000 | 1 | http://localhost:40000/dtale/main/1 |
| 2 | 40002 | 1 | http://localhost:40002/dtale/main/1 |
- Session 4 executes
dtale.show(df, port=8080)our state is:
| Session | Port | Active Data IDs | URL(s) |
|---|---|---|---|
| 1 | 40001 | 1,2,3 | http://localhost:40001/dtale/main/[1,2,3] |
| 3 | 40000 | 1 | http://localhost:40000/dtale/main/1 |
| 2 | 40002 | 1 | http://localhost:40002/dtale/main/1 |
| 4 | 8080 | 1 | http://localhost:8080/dtale/main/1 |
- Session 1 executes
dtale.get_instance(1).kill()our state is:
| Session | Port | Active Data IDs | URL(s) |
|---|---|---|---|
| 1 | 40001 | 2,3 | http://localhost:40001/dtale/main/[2,3] |
| 3 | 40000 | 1 | http://localhost:40000/dtale/main/1 |
| 2 | 40002 | 1 | http://localhost:40002/dtale/main/1 |
| 4 | 8080 | 1 | http://localhost:8080/dtale/main/1 |
- Session 5 sets DTALE_MIN_RANGE to 30000 and DTALE_MAX_RANGE 39000 and executes
dtale.show(df)our state is:
| Session | Port | Active Data ID(s) | URL(s) |
|---|---|---|---|
| 1 | 40001 | 2,3 | http://localhost:40001/dtale/main/[2,3] |
| 3 | 40000 | 1 | http://localhost:40000/dtale/main/1 |
| 2 | 40002 | 1 | http://localhost:40002/dtale/main/1 |
| 4 | 8080 | 1 | http://localhost:8080/dtale/main/1 |
| 5 | 30000 | 1 | http://localhost:30000/dtale/main/1 |
Have a look at the detailed documentation.
D-Tale works with:
- Back-end
- arctic
- Flask
- Flask-Caching
- Flask-Compress
- flasgger
- Pandas
- scipy
- six
- Front-end
- react-virtualized
- chart.js
D-Tale has been under active development at Man Numeric since 2019.
Original concept and implementation: Andrew Schonfeld
Contributors:
- Wilfred Hughes
- Dominik Christ
- Chris Boddy
- Jason Holden
- Tom Taylor
- Vincent Riemer
- Fernando Saravia Rajal
- Mike Kelly
- Youssef Habchi - title font
- ... and many others ...
Contributions welcome!
D-Tale is licensed under the GNU LGPL v2.1. A copy of which is included in LICENSE