I have a set of data that has a X number of points and I want to re size this to x+n number of points.
I need to do this with tcl and am struggling in the last part.
I know the Max, Min and the delta that is needed to refit the data to desired number of points.
Original data:
-0.3925
-0.262
-0.1965
-0.026
-0.013
-0.0065
-0.0026
0
0.0026
0.0065
0.013
0.026
0.1965
0.262
0.3925
I'm struggling to construct a for loop that will, take the first value and subtract it from delta to create the second value. Subsequently take the second and subtract it from delta to create third and so on and so forth.
Given:
Points 19
Min : -0.3925
Max :0.3925
Delta : 0.04361
Results column data would look like:
-0.3925
-0.348888889
-0.305277778
-0.261666667
-0.218055556
-0.174444444
-0.130833333
-0.087222222
-0.043611111
-6.93889E-17
0.043611111
0.087222222
0.130833333
0.174444444
0.218055556
0.261666667
0.305277778
0.348888889
0.3925
Could someone kindly give me some advice.
There are a few key points when doing this sort of thing (and these apply to languages other than Tcl too). Firstly, you should compute the delta from the span you want and the number of steps you want. Secondly, you should keep your incrementing and loop control using integers if you can, so as to avoid fencepost errors caused by rounding; instead compute the value for the loop iteration by multiplying the delta by the loop counter and adding to the originating value. Thirdly, you should consider what the right precision is when printing your results; in Tcl, this tends to mean using format with the %f conversion and appropriate width specifier.
set from -0.3925
set to 0.3925
set points 19
set delta [expr {($to-$from) / double($points-1)}]
for {set i 0} {$i<$points} {incr i} {
set x [expr {$from + $i*$delta}]
puts [format "%.5f" $x]
}
This produces this output:
-0.39250
-0.34889
-0.30528
-0.26167
-0.21806
-0.17444
-0.13083
-0.08722
-0.04361
0.00000
0.04361
0.08722
0.13083
0.17444
0.21806
0.26167
0.30528
0.34889
0.39250
Related
Given a dataset of blood results, say cholesterol level, and knowing that the instrument that produced those results is subject to a known degree of variability, how would I add that variability back into the dataset? i.e. I want to assume the result in the original dataset is the true/mean value, and then produce new results that are subject to the known variability of the instrument.
In Excel you use =NORM.INV(RAND(), mean, std_dev), where RAND() provides a random value between 0 and 1, "mean" will be the original value and I have the CV so I can calculate the SD. NORM.INV then provides the inverse of the cumulative normal distribution function.
I've done the following to create a new column with my new values, but would like to know if it is valid (i.e., will each row have a different random number between 0 and 1 as the probability? and is this formula equivalent to NORM.INV?
df8000['HDL_1'] = norm.ppf(random(), loc = df8000['HDL_0'], scale = TAE_df.loc[0,'HDL'])
Thanks in advance!
so this is what I'm trying to do, and I'm not sure how cause I'm new to python. I've searched for a few options and I'm not sure why this doesn't work.
So I have 6 different nodes, in maya, called aiSwitch. I need to generate random different numbers from 0 to 6 and input that value in the aiSiwtch*.index.
In short the result should be
aiSwitch1.index = (random number from 0 to 5)
aiSwitch2.index = (another random number from 0 to 5 different than the one before)
And so on unil aiSwitch6.index
I tried the following:
import maya.cmds as mc
import random
allswtich = mc.ls('aiSwitch*')
for i in allswitch:
print i
S = range(0,6)
print S
shuffle = random.sample(S, len(S))
print shuffle
for w in shuffle:
print w
mc.setAttr(i + '.index', w)
This is the result I get from the prints:
aiSwitch1 <-- from print i
[0,1,2,3,4,5] <--- from print S
[2,3,5,4,0,1] <--- from print Shuffle (random.sample results)
2
3
5
4
0
1 <--- from print w, every separated item in the random.sample list.
Now, this happens for every aiSwitch, cause it's in a loop of course. And the random numbers are always a different list cause it happens every time the loop runs.
So where is the problem then?
aiSwitch1.index = 1
And all the other aiSwitch*.index always take only the last item in the list but the time I get to do the setAttr. It seems to be that w is retaining the last value of the for loop. I don't quite understand how to
Get a random value from 0 to 5
Input that value in aiSwitch1.index
Get another random value from 0 to 6 different to the one before
Input that value in aiSwitch2.index
Repeat until aiSwitch5.index.
I did get it to work with the following form:
allSwitch = mc.ls('aiSwitch')
for i in allSwitch:
mc.setAttr(i + '.index', random.uniform(0,5))
This gave a random number from 0 to 5 to all aiSwitch*.index, but some of them repeat. I think this works cause the value is being generated every time the loop runs, hence setting the attribute with a random number. But the numbers repeat and I was trying to avoid that. I also tried a shuffle but failed to get any values from it.
My main mistake seems to be that I'm generating a list and sampling it, but I'm failing to assign every different item from that list to different aiSwitch*.index nodes. And I'm running out of ideas for this.
Any clues would be greatly appreciated.
Thanks.
Jonathan.
Here is a somewhat Pythonic way: shuffle the list of indices, then iterate over it using zip (which is useful for iterating over structures in parallel, which is what you need to do here):
import random
index = list(range(6))
random.shuffle(index)
allSwitch = mc.ls('aiSwitch*')
for i,j in zip(allSwitch,index):
mc.setAttr(i + '.index', j)
I am writing a simple code in matlab which has the purpose of creating the histogram of a grayscale image without using the function hist. I am stuck at the point in which mathlab displays the error "Subscript indices must either be real positive integers or logicals." Can you help me finding where is the wrong indices?
indirizzo='file.jpg';
immagine=imread(indirizzo);
immaginebn=rgb2gray(immagine);
n=zerps(0,255);
for x=0:255;
numeroennesimo=sum(sum(immaginebn==x));
n(x)=numeroennesimo;
end
plot(x,n)
you cant use 0 as index. Either make n(x+1) or for x = 1:256 and substract the 1 in your comparison. And there is a typo, I guess it means zeros instead of zerps, which also doesnt work with a 0. And one more, your plot will also not work as the x has only a size of 1 while n is an array of 266 and for a histogram I would use a barplot instead.
indirizzo='file.jpg';
immagine=imread(indirizzo);
immaginebn=rgb2gray(immagine);
n=zeros(1,256);
for x=0:255;
numeroennesimo=sum(sum(immaginebn==x-1));
n(x+1)=numeroennesimo;
end
bar(0:255,n)
or
indirizzo='file.jpg';
immagine=imread(indirizzo);
immaginebn=rgb2gray(immagine);
n=zeros(1,256);
xplot=zeros(1,256);
for x=1:256;
numeroennesimo=sum(sum(immaginebn==x-1));
n(x)=numeroennesimo;
xplot(x) = x-1;
end
plot(xplot,n)
I have a 250*2001 matrix. I want to find the location for the maximum value for a(:,i) where i takes 5 different values: i = i + 256
a(:,256)
a(:,512)
a(:,768)
a(:,1024)
a(:,1280)
I tried using MAXLOC, but since I'm new to fortran, I couldn't get it right.
Try this
maxloc(a(:,256:1280:256))
but be warned, this call will return a value in the range 1..5 for the second dimension. The call will return the index of the maxloc in the 2001*5 array section that you pass to it. So to get the column index of the location in the original array you'll have to do some multiplication. And note that since the argument in the call to maxloc is a rank-2 array section the call will return a 2-element vector.
Your question is a little unclear: it could be either of two things you want.
One value for the maximum over the entire 250-by-5 subarray;
One value for the maximum in each of the 5 250-by-1 subarrays.
Your comments suggest you want the latter, and there is already an answer for the former.
So, in case it is the latter:
b(1:5) = MAXLOC(a(:,256:1280:256), DIM=1)
I have a bunch of values, for example: [1,2,14,51,100,103,107,110,300,505,1034].
And I have a pattern values, for example [1,10,20,100,500,1000].
I need to get the best 'suitable' value FROM pattern. In my example it is 100. How can I detect this value?
Example from life. The app has a bunch of distances between user position and some objects. The app also has a preset filter by distance: [1 meter, 10 meters, 20 meters, 100 meters]. I heed to set the filter by default not just to the first value (1 meter in my example), but to the value which match the bunch of distances the best way(100 meter in my example). I need to detect one value.
Thank you for help and any ideas.
I would say create a function like this (this is not real code) :
var ratio1 = 0.66
var ratio2 = 1.5
function Score(currentPatternValue, arrayOfValues)
{
count = 0
for each value in arrayOfValues <br>
if value > ratio1 * currentPatternValue AND value < ratio2 * currentPatternValue<br>
count++<br>
return count
}
then you run this for each value in your pattern values and pick the one with the highest score returned from that function