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Jason
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Binning a column vector to certain values (includes negative values)

Asked by Jason
on 12 Sep 2019
Latest activity Edited by Jason
on 12 Sep 2019
Hello, I have a sey of X, Y coordinates that I am using for plotting a heatmap. My X & Y coordiantes are from a microscope stage and so vary slightly:
I move my stage in X&Y in steps of 500.
So my real data is typically:
X Y
0.1 0.2
-0.2 501
0.3 1000.5
-0.4 1502
-501 -0.1
-503 501
-500 1000.1
-499 1503
etc.
How can I make my data so both X & Y (both can be positive or negative) be binned into e.g.
X Y
0 0
0 500
0 1000
0 1500
-500 0
-500 1000
-500 1500
I tried the digitizer but it had NaN's in it,
data = [0 -0.2 -0.1 0 0.1 0 2 0.1 -0.1 0.2]
data =
0 -0.20 -0.10 0 0.10 0 2.00 0.10 -0.10 0.20
>> edges = 0:500:5000
edges =
0 500.00 1000.00 1500.00 2000.00 2500.00 3000.00 3500.00 4000.00 4500.00 5000.00
>> [Y,E] = discretize(data,edges)
Y =
1.00 NaN NaN 1.00 1.00 1.00 1.00 1.00 NaN 1.00
E =
0 500.00 1000.00 1500.00 2000.00 2500.00 3000.00 3500.00 4000.00 4500.00 5000.00

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1 Answer

回答者: Steven Lord
2019 年 9 月 12 日

The left edge of your first bin should be less than than the first value you want included in that bin. Right now, -0.2 doesn't fit into any of the bins; it's to the left of the first bin. If you change the first element of your edges vector to something less than -0.2 (as an extreme example that will guarantee everything smaller than 500 is in the first bin, use -Inf) it will include those negative values.

  1 Comment

Jason
2019 年 9 月 12 日
So If I assume all my steps are about 500 and the max error in each could be +/- 5.
How would I go about defining the bins say from -10000 to 10000 with steps of -500 with an error of +/- 5 on each bin edge
so would want
-10005 to -9995 to be -10000
...
..
-5 to 5 to be 0
etc

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