# How to plot geographical values against a parameter in a color map graph

조회 수: 1 (최근 30일)
댓글: Anna S 2020년 8월 28일
I have a excel file consisting of 4 columns. The first column is the sample number. The 2nd and 3rd are the geographical lat/long. The last column is the moisture values.
I need to plot a graph that shows the moisture of these points in a form of a color map. I attach my file. Can anyone help me? Thanks
##### 댓글 수: 1이전 댓글 -1개 표시이전 댓글 -1개 숨기기
darova 2019년 8월 10일
Maybe plotm() or scatterm()?

댓글을 달려면 로그인하십시오.

### 답변 (1개)

Parivash,
The first step is importing the data into Matlab. Unfortunately the lat and lon data are in degrees-minutes-decimal-seconds format, so xlsread might have some trouble with it. Maybe try removing all the degree symbols and import as space-delimited columns.
The next step is converting the dms format to decimal degrees, which you can do with dms2degrees if you have the Mapping Toolbox, or you can convert manually just by adding up the fractions of a degree and the fractions of a minute.
Then you'll have lon and lat in decimal degrees, and corresponding moisture values m. You can plot this as a color-scaled plot with the scatter function like
scatter(lon,lat,30,m,'filled')
and if you'd like to change the colormap you might like the cmocean rain colormap for moisture.
##### 댓글 수: 1이전 댓글 -1개 표시이전 댓글 -1개 숨기기
Anna S 2020년 8월 28일
Ah okay, so probably that is the problem of my dataset, because the interpolation of non-equally spaced and 'randomly' distributed grid points causes an error in creating the 'interpolated grid'.
Thanks!

댓글을 달려면 로그인하십시오.

### 카테고리

Help CenterFile Exchange에서 Geographic Plots에 대해 자세히 알아보기

### Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by