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Why am I unable to make a plot containing subplots in plotly using a px.scatter plot?

I have been trying to make a figure using plotly that combines multiple figures together. In order to do this, I have been trying to use the make_subplots function, but I have found it very difficult to have the plots added in such a way that they are properly formatted. I can currently make singular plots (as seen directly below):
However, whenever I try to combine these singular plots using make_subplots, I end up with this:
This figure has the subplots set up completely wrong, since I need each of the four subplots to contain data pertaining to the four methods (A, B, C, and D). In other words, I would like to have four subplots that look like my singular plot example above.
I have set up the code in the following way:
for sequence in sequences:
#process for making sequence profile is done here
sequence_df = pd.DataFrame(sequence_profile)
row_number=1
grand_figure = make_subplots(rows=4, cols=1)
#there are four groups per sequence, so the grand figure should have four subplots in total
for group in sequence_df["group"].unique():
figure_df_group = sequence_df[(sequence_df["group"]==group)]
figure_df_group.sort_values("sample", ascending=True, inplace=True)
figure = px.line(figure_df_group, x = figure_df_group["sample"], y = figure_df_group["intensity"], color= figure_df_group["method"])
figure.update_xaxes(title= "sample")
figure.update_traces(mode='markers+lines')
#note: the next line fails, since data must be extracted from the figure, hence why it is commented out
#grand_figure.append_trace(figure, row = row_number, col=1)
figure.update_layout(title_text="{} Profile Plot".format(sequence))
grand_figure.append_trace(figure.data[0], row = row_number, col=1)
row_number+=1
figure.write_image(os.path.join(output_directory+"{}_profile_plot_subplots_in_{}.jpg".format(sequence, group)))
grand_figure.write_image(os.path.join(output_directory+"grand_figure_{}_profile_plot_subplots.jpg".format(sequence)))
I have tried following directions (like for example, here: ValueError: Invalid element(s) received for the 'data' property) but I was unable to get my figures added as is as subplots. At first it seemed like I needed to use the graph object (go) module in plotly (https://plotly.com/python/subplots/), but I would really like to keep the formatting/design of my current singular plot. I just want the plots to be conglomerated in groups of four. However, when I try to add the subplots like I currently do, I need to use the data property of the figure, which causes the design of my scatter plot to be completely messed up. Any help for how I can ameliorate this problem would be great.

Ok, so I found a solution here. Rather than using the make_subplots function, I just instead exported all the figures onto an .html file (Plotly saving multiple plots into a single html) and then converted it into an image (HTML to IMAGE using Python). This isn't exactly the approach I would have preferred to have, but it does work.
UPDATE
I have found that plotly express offers another solution, as the px.line object has the parameter of facet that allows one to set up multiple subplots within their plot. My code is set up like this, and is different from the code above in that the dataframe does not need to be iterated in a for loop based on its groups:
sequence_df = pd.DataFrame(sequence_profile)
figure = px.line(sequence_df, x = sequence_df["sample"], y = sequence_df["intensity"], color= sequence_df["method"], facet_col= sequence_df["group"])
Although it still needs more formatting, my plot now looks like this, which is works much better for my purposes:

Grouped bar chart of multiindex

first of all: I'm completely new to python.
I'm trying to visualize some measured data. Each entry has a quadrant, number and sector. The original data lies in a .xlsx file. I've managed to use a .pivot_table to sort the data according to its sector. Due to overlapping, number and quadrant also have to be indexed. Now I want to plot it as a bar chart, where the bars are grouped by sector and the colors represent the quadrant.
But because number also has to be indexed, it shows up in the bar chart as a separate group. There should only be three groups, 0, i and a.
MWE:
import pandas as pd
import matplotlib.pyplot as plt
import numpy as np
d = {'quadrant': ["0","0","0","0","0","0","I","I","I","I","I","I","I","I","I","I","I","I","II","II","II","II","II","II","II","II","II","II","II","II","III","III","III","III","III","III","III","III","III","III","III","III","IV","IV","IV","IV","IV","IV","IV","IV","IV","IV","IV","IV"], 'sector': [0,"0","0","0","0","0","a","a","a","a","a","a","i","i","i","i","i","i","a","a","a","a","a","a","i","i","i","i","i","i","a","a","a","a","a","a","i","i","i","i","i","i","a","a","a","a","a","a","i","i","i","i","i","i"], 'number': [1,2,3,4,5,6,1,2,3,4,5,6,1,2,3,4,5,6,1,2,3,4,5,6,1,2,3,4,5,6,1,2,3,4,5,6,1,2,3,4,5,6,1,2,3,4,5,6,1,2,3,4,5,6], 'Rz_m': [67.90,44.17,44.30,63.43,49.87,39.33,61.17,69.37,66.20,44.20,64.77,39.93,44.33,50.97,55.90,51.33,58.23,44.53,50.03,47.40,58.67,71.57,57.60,70.77,63.93,47.37,46.90,34.73,41.27,48.23,58.30,47.07,50.53,51.20,32.67,50.37,37.50,55.50,41.20,48.07,56.80,49.77,40.87,44.43,44.00,60.03,63.73,72.80,51.60,45.53,60.27,71.00,59.63,48.70]}
df = pd.DataFrame(data=d)
B = df.pivot_table(index=['sector','number', 'quadrant'])
B.unstack().plot.bar(y='Rz_m')

The data viz ecosystem in Python is pretty diverse and there are multiple libraries you can use to produce the same chart. Matplotlib is a very powerful library, but it's also quite low-level, meaning you often have to do a lot of preparatory work before getting to the chart, so usually you'll find people use seaborn for static visualisations, especially if there is a scientific element to them (it has built-in support for things like error bars, etc.)
Out of the box, it has a lot of chart types to support exploratory data analysis and is built on top of matplotlib. For your example, if I understood it right, it would be as simple as:
import seaborn as sns
sns.catplot(x="sector", y="Rz_m", hue="quadrant", data=df, ci=None,
height=6, kind="bar", palette="muted")
And the output would look like this:
Note that in your example, you missed out "" for one of the zeroes and 0 and "0" are plotted as separate columns. If you're using seaborn, you don't need to pivot the data, just feed it the df as you've defined it.
For interactive visualisations (with tooltips, zoom, pan, etc.), you can also check out bokeh.
There is an interesting wrinkle to this - how to center the nested bars on the label. By default the bars are drawn with center alignment which works fine for an odd number of columns. However, for an even number, you'd want them to be centered on the right edge. You can make a small alteration in the source code categorical.py, lines beginning 1642 like so:
# Draw the bars
offpos = barpos + self.hue_offsets[j]
barfunc(offpos, self.statistic[:, j], -self.nested_width,
color=self.colors[j], align="edge",
label=hue_level, **kws)
Save the .png and then change it back, but it's not ideal. Probably worth flagging up to the library maintainers.

Indexing my dataframe properly with pandas

I'm trying to plot a bargraph with errorbars acquired from my tests, i found some code on the internet on how to make it. But the code does not fit the way i want the table to look like.
I've tried leaving things out however i don't understand the dataframe enough to know what kind of code i need to process the data correctly.
order=pd.MultiIndex.from_arrays([['402515','402515','402515','402510','402510','402510'],
['z','z','z','z','z','z']],names=['letter','word'])
datas=pd.DataFrame({'first cracking strength':[em1,em2,em3,em4,em5,em6],'flexural strength':[en1,en2,en3,en4,en5,en6]},index=order)
gp4 = datas.groupby(level=('letter', 'word'))
means = gp4.mean()
errors = gp4.std()
print(means)
fig, ax = plt.subplots()
means.plot.bar(yerr=errors, ax=ax, capsize=4);
The multi-index code requires two labels (the 'z' and the '402515/402510', I only want the '402515/402510') on your dataset, but I only want one. What other code does that?
How it looks when I run the code.
How I want it to look.

Why do sns.lmplot and FacetGrid+plt.scatter create different scatter points from the same data?

I'm quite new to Python, pandas DataFrames and Seaborn. When I was trying to understand Seaborn better, particularly sns.lmplot, I came across a difference between two figures made of the same data, that I thought were supposed to look alike, and I wonder why that is.
Data: My data is a pandas DataFrame that has 454 rows and 19 columns. The data relevant to this question includes 4 columns and looks something like this:
Columns: Av_density; pred2; LOC; Year;
Variable type: Continuous variable; Continuous variable; Categorical variable 1...4;Categorical 2012...2014
There are no missing data points.
My aim is to draw a 2x2 figure panel describing the relationship between Av_density and pred2 separately for each LOC(=location) with years marked with different colours. I call seaborn with:
import seaborn as sns
sns.set(style="whitegrid")
np.random.seed(sum(map(ord, "linear_categorical")))
(Side point: for some reason calling "linear_quantitative" does not work, i.e. I get a "File "stdin", line 2
sns.lmplot("Av_density", "pred2", Data, col="LOC", hue="YEAR", col_wrap=2);
^
SyntaxError: invalid syntax")
Figure method 1, FacetGrid + scatter:
sur=sns.FacetGrid(Data,col="LOC", col_wrap=2,hue="YEAR")
sur.map(plt.scatter, "Av_density", "pred2" );
plt.legend()
This produces a nice scatter of the data accurately. You can see the picture here:https://drive.google.com/file/d/0B7h2wsx9mUBScEdUbGRlRk5PV1E/view?usp=sharing
Figure method 2, sns.lmplot:
sns.lmplot("Av_density", "pred2", Data, col="LOC", hue="YEAR", col_wrap=2);
This produces the figure panel divided by LOC accurately, with Years in different colours, but the scatter of the data points does not look right. Instead, it looks like lmplot has linearised the data points, and lost the original scatter points that it is supposed to be drawing in addition to the regression lines.
You can see the figure here: https://drive.google.com/file/d/0B7h2wsx9mUBSRkN5ZXhBeW9ob1E/view?usp=sharing
My data produces only three points per location per year, and I was first wondering if this is what makes the "mistake" in lmplot datapoint. Optimally I would have a shorter line describing the trend between years instead of a proper regression, but I have not figured out the code to this yet.
But before tackling that issue, I would really like to know if there is something I am doing wrong that I can fix, or if this is an issue of lmplot trying to handle my data?
Any help, comments and ideas on this are warmly welcome!
-TA-
Ps. I'm running Python 2.7.8 with Spyder 2.3.4
EDIT: I get shorter "trend lines" with the first method by adding:
sur.map(plt.plot,"Av_density", "pred2" );
Still would like to know what is messing the figure with lmplot.

The issue is probably only that the added regression line is messing up the y-axis, so that the variability in the data cannot be seen.
Try resetting the y-axis based on the variability in your original plot to see if they show the same thing, in your case e.g.
fig1 = sns.lmplot("Av_density", "pred2", Data, col="LOC", hue="YEAR", col_wrap=2);
fig1.set(ylim=(-0.03, 0.05))
plt.show(fig1)

Gnuplot: Plotting one series per line of input values

I have a CSV file that looks like this:
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[...]
I want to be able to plot a new series per line (legend not necessary). The x-values should just start at 0 and increment from there, the y-values are given by the numbers in the file. The result should be something like this:
This was made in Excel, and if it weren't so labourous, this would be fine.
Note that answers using python/matplotlib are also welcomed.
Thanks a lot!
EDIT: This is as far as I've come, based on the answer provided in gnuplot: How to plot each line of a data file as Y and incremental X and other places. So far, there's for some reason no output file written, although it's definitely doing something (because the last command takes a few seconds to finish).
set term png
set output "fft.png"
set datafile sep ','
plot for [i=1:255] 'fft.csv' using (i):(column(i)) with lines
EDIT 2: I now have this, which is closer, but still not what I want. Each line in the input file should be a series. It seems now each column is a series.
set term png
set output "fft.png"
set datafile sep ','
unset key
plot for [i=1:255] 'fft.csv' using (i):(column(i)) with lines

Right, I think I solved it (using the answer from https://stackoverflow.com/a/8716495/666259 and the answer from Christoph):
set terminal png size 1920,1080
set datafile sep ","
unset key
set xtics 0,5,255
set title "mytitle"
set autoscale cbfix
plot "fft.csv" matrix using 1:3:2 with lines palette
This gives me something like this:

In order to have every line with a different color, use either palette or linecolor variable:
set datafile separator ','
set autoscale cbfix
plot 'file.csv' matrix every :::1 using 1:3:2 with lines palette
This uses the row number to color the lines based on the current palette. This is very useful if you have many lines to draw. set autoscale cbfix prevents the color range to be extended to the next major tics.
For only a few lines, you could also use
plot 'file.csv' matrix every :::1 using 1:3:2 linecolor variable with lines
This uses the row number as index for the linetype.