Answered

Fill data with NaN for missing days

I finally did it although using a loop: %create a index column first first_nan(:, 1) = 1:365; %compare the A matrix ...

Fill data with NaN for missing days

I finally did it although using a loop: %create a index column first first_nan(:, 1) = 1:365; %compare the A matrix ...

plus d'un an ago | 0

Question

Fill data with NaN for missing days

I have a matrix A in which I have number of days in first column and corresponding data in the second column. For example, A (...

plus d'un an ago | 1 answer | 0

Question

Combine(mosaic) geolocated Earth data horizontally

Hi, I am processing MODIS level 2 data granules in hdf format. Reading one granule, I get one 203*135 sized 'latitude' matrix, a...

plus d'un an ago | 0 answers | 0

Question

nanmean gives unexpected results

I am calculating nanmean using two different techniques. I have a matrix avg_terra_aqua1 of size 28*360000. In the first method,...

plus d'un an ago | 1 answer | 0

Question

Using horzcat in a loop for combining large number of files

hi, I need to combine 100 matrices horizontally using horzcat. I have a matrix named 'data' of size 20*30*100 in which 100 repr...

environ 2 ans ago | 1 answer | 0

Question

indices when the columns are all nan

I am using [m, d] = nanmax (r_all); to get the maximum values and corresponding indices in matlab. There are several columns in ...

plus de 3 ans ago | 2 answers | 0

Answered

Formula for cross-correlation in matlab

It looks like that 'xcorr' does not calculate Pearson correlation coefficient directly. To get Pearson correlation coefficient, ...

Formula for cross-correlation in matlab

It looks like that 'xcorr' does not calculate Pearson correlation coefficient directly. To get Pearson correlation coefficient, ...

plus de 3 ans ago | 0

| accepted

Question

Formula for cross-correlation in matlab

When we calculate cross correlation using the function 'xcorr' with 'coeff' option, does the function calculate Pearson correlat...

plus de 3 ans ago | 2 answers | 0

Question

hide NaNs in geoshow

I am plotting some data using geoshow as below: geoshow (yy, xx, data, 'displaytype', 'texturemap'); The 'data' has a lot of NaN...

presque 4 ans ago | 2 answers | 0

Answered

Percentage of contribution of multiple factors to a single dependent variable using PCA in Matlab

Unfortunately, PCA may not be the tool for what you are looking for. PCA is more suitable when the number of variables is large ...

Percentage of contribution of multiple factors to a single dependent variable using PCA in Matlab

Unfortunately, PCA may not be the tool for what you are looking for. PCA is more suitable when the number of variables is large ...

environ 4 ans ago | 0

Answered

Input for PCA function

Depending on your objective, you can probably consider 'd' as another variable. In such a case, put a, b, c, and d in four colum...

Input for PCA function

Depending on your objective, you can probably consider 'd' as another variable. In such a case, put a, b, c, and d in four colum...

environ 4 ans ago | 0

Answered

PCA scaling and centering documentation wrong?

You got it little wrong. When you do PCA(Y), by default, PCA again centers the data. So if you want to get the same values as PC...

PCA scaling and centering documentation wrong?

You got it little wrong. When you do PCA(Y), by default, PCA again centers the data. So if you want to get the same values as PC...

environ 4 ans ago | 0

Answered

Distinguish between 2 variables using PCA

PCA can certainly give some insights in your problem. Run PCA in your data and look at the different principal components. In yo...

Distinguish between 2 variables using PCA

PCA can certainly give some insights in your problem. Run PCA in your data and look at the different principal components. In yo...

environ 4 ans ago | 0

Answered

pca: missing first pc

Your question is not clear, pca(X) will give coefficient matrix whose first column represents coefficients of the first principa...

pca: missing first pc

Your question is not clear, pca(X) will give coefficient matrix whose first column represents coefficients of the first principa...

environ 4 ans ago | 0

| accepted

Answered

Interpreting outputs of pca function

In short, you cannot attribute one principal component to a particular variable, because by definition, a principal component is...

Interpreting outputs of pca function

In short, you cannot attribute one principal component to a particular variable, because by definition, a principal component is...

environ 4 ans ago | 0

Question

cross correlation using 'xcorr' in the presence of NaN or missing values

Hi I am trying to calculate cross correlation of two time-series at different lags but my data have a lot of NaN values. When I ...

environ 4 ans ago | 0 answers | 0

Question

using 'als' algorithm in pca

I am doing PCA using 'als' algorithm as below. When I specify a specific number of components (1 here), the 'explained' term giv...

environ 4 ans ago | 0 answers | 0

Question

nancov gives strange results

I have a standardized matrix (aod_normalized) of a variable whose size is 3653*12, where 3653 is the no. of observations and 12 ...

environ 4 ans ago | 1 answer | 0

Answered

plotting lat, lon, altitude, variable

Never mind! I was able to plot as I wanted with a small tweak. This is what I did: load ('coast.mat'); long (lo...

plotting lat, lon, altitude, variable

Never mind! I was able to plot as I wanted with a small tweak. This is what I did: load ('coast.mat'); long (lo...

plus de 4 ans ago | 0

Question

plotting lat, lon, altitude, variable

I have 3 vectors of latitude, longitude, and elevation respectively. I also have a corresponding 3d matrix of size latitude*long...

plus de 4 ans ago | 4 answers | 0

Question

how to run a function in each cells?

Hi, I am using a function 'taylordiag' as follows: [ hp, ht, axl ] = taylordiag ( stn { 1 } (2, : ), stn { 1 } ( 3, : ), stn {...

environ 5 ans ago | 1 answer | 0

Question

How to calculate correlation coefficient between two 3-d matrices?

This is often required in analyzing climate data from netcdf files. Climate variables are stored in 3-d matrix (lat, lon, time)....

environ 5 ans ago | 2 answers | 0

Question

How to rotate entire 3d data with x,y,z values along a particular axis (say x axis)?

I need to rotate my 3d dataset defined by x,y,z coordinate along x axis at a specified angle (say 45 degree). This kinds of rota...

plus de 5 ans ago | 2 answers | 0