ansaurus

Question

How to scale down the y-axis in matplotlib/python?

Answer 1

+1 A:

You can just do a simple linear transformation, for all y's:

ynew= 2*(y-ymin)/(ymax-ymin)

The fraction (y-ymin)/(ymax-ymin) first gives you the percentage of the y coordinate in the range you are interested in, and then to get it from range 0-1 into range 0-2, you just multiply by 2.

karpathy 2010-08-03 00:04:15

Would this work if my values were a bunch of deltas. So I wanted the initial y_value to be centered at y=1 and the rest of the values between y=0 and y=2 depending on their delta to the initial y_value.

bassngo 2010-08-03 00:12:51

But what if ymin is off more from yinit than ymax is? Would you want to "squish" the top and bottom differently to make sure it definitely all lies in [0,2] ? That's probably not what you are looking for.

karpathy 2010-08-03 00:22:34

I think you want to do something like this:M= max(abs(yinit-ymin), abs(yinit-ymax))the for all y's:ynew= (y-yinit)/M +1

karpathy 2010-08-03 00:25:34

why do you have to divide by M+1?

bassngo 2010-08-03 00:48:44

no :) you divide by M, and then at the end add 1 :) since that's where you want it centered.

karpathy 2010-08-03 04:53:30

ansaurus

tags:

views:

answers:

How to scale down the y-axis in matplotlib/python?

related questions