Use for questions concerning the Python based Graphics Pipeline which is meant for building visualizations of large data sets.
Datashader is a python graphics pipeline system for creating meaningful representations of large amounts of data.
Questions tagged [datashader]
123 questions
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Big data scatterplot adding lines
I need a scatterplot for a dataset with 77M+ rows, plus adding lines like the plt.axlines.
import pandas as pd
import numpy as np
import matplotlib.pyplot as plt
df = pd.DataFrame({ 'x' :np.random.normal(0,1,77000000),
'y' :…
VYago
- 325
- 2
- 9
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How do I plot an irregularly gridded RGB using holoview QuadMesh?
I am working with irregularly gridded earth observation data, and am trying to find ways to plot this efficiently using holoview with bokeh as the backend. I wish to avoid interpolation if at all possible.
Plotting regularly gridded data seems…
Ben
- 3
- 3
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1 answer
How can I set up the correct color image color in datashader?
I have tried to plot a given example from the datashader page about Timeseries. I used all the code snippets including this paragraph and tried to plot the img with matplotlib by passing the img to the plt.imshow(img):
import datetime
import pandas…
Rene
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1 answer
NetworkX: drawing large graphs?
I have a graphML file that represents relation between multiple SQL tables (nodes and edges).
I am using networkx to parse the file and matplotlib to draw it. The issue I have is that my graph is quite big (around 150 nodes) and hard to read. I do…
Pierre-Alexandre
- 543
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Strange behaviour of datashader with aggregate=ds.by(color, any())
Software-versions
pandas: 1.3.3,
datashader: 0.13.0,
bokeh: 2.3.3,
holoviews: 1.14.6
What I want to achieve/My current problem
I do some scatterplots of categorical data with bokeh/holoviews. Sometimes the sets are big so I want to use…
Noskario
- 378
- 1
- 9
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1 answer
Holoviews "Points" working with Datashader but "Curve" is throwing an error
I'm working with large data (~25million points) in Python in Jupyter Notebook and want to have an interactive graph that also doesn't take forever to load. Using Bokeh gives me the interactivity and Holoviews and Datashader allows the data to be…
Michael S.
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1 answer
Geotiff overlay position is slightly off on Holoviews/Bokeh tilemap
I have a Geotiff that I display on a tile map, but it's slightly off to the south. For example, on this screenshot the edge of the image should be where the country border is, but it's a bit to the south:
Here's the relevant part of the…
SteveAKopias
- 11
- 5
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Add datashader to matplotlib subplots - Positional arguments error
I want to use datashader output as an input into a plt subplot.
I am trying to run the code suggested in the answer to this question:
Add datashader image to matplotlib subplots
Here is the code below:
from datashader.mpl_ext import DSArtist
import…
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Plotting with datashader from an xarray DataArray with a Datetime dimension
I have an xarray DataArray that is 2d. One dimension is frequency and the other is time. When creating the DataArray I specify the coordinates.
data = np.memmap(fname, np.float32, mode="c")
dx = xr.DataArray(data, coords=[dt,freqs], dims=["Time",…
ofionnad
- 41
- 1
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votes
1 answer
Bokeh + Holoviews + Datashader on Django
We are trying to build a web app--Dashboard-- to show different interactive(including click callback, fetch new data etc) charts with Bokeh + Holoviews + Datashader on DJango.
Since data is very large and could have 10+ million points we are using…
Mukesh Kumar
- 333
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- 20
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0 answers
TypeError: Cannot cast array data from dtype('int64') to dtype('int32') according to the rule 'safe' with hvPlot and datashade
I've try using this tutorial https://holoviz.org/tutorial/Basic_Plotting.html to use datashade in hvPlot, but with personnal data.
I can show my plot with df.hvplot.scatter(x='col1', y='col2', datashade=False) for n number of line, but when I try to…
LordOptimistic
- 27
- 1
- 5
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votes
1 answer
data shader change color for each date
For a scatterplot with datashader I want to incorporate the notion of time into the plot. Potentially by using color.
Currently,
import numpy as np
import pandas as pd
import seaborn as sns
date_values = ['2020-01-01', '2020-01-02', '2020-01-03',…
Georg Heiler
- 16,916
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- 292
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1 answer
Working with Dask, Xarray, Holoviews, Bokeh Datasets
Currently have very large xarray dataset with 7 data variables, each with shape of about 60-80k (x,y) values as well as 4 years (give or take) of time data. Im working on creating a UI that will display 3 maps, 1 main map and 2 maps shown below of a…
Nathan Smith
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- 2
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1 answer
Wider points cuxfilter / Datashader scatter?
How can I get wider points to display in this datashader.scatter plot of cuxfilter? Or less whitespace between columns? This is a scatter plot of passenger_count (x) vs tip_amount (y) on some TLC yellow cab trip data.
The goal is to have something…
gumdropsteve
- 70
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- 14
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1 answer
Holoviews active tools configuration and datashader layout
Suppose having the following code:
# Layout creation
y1 = hv.Curve((dt, data['Noise 1']), 'Date', 'y(t)', label='Noise 1')
y2 = hv.Curve((dt, data['Noise 2']), 'Date', 'y(t)', label='Noise 2')
layout = y1 + y2
# Grid style layout
gridstyle = {
…
