how to save the map information in a structure?

3 views (last 30 days)
kuldeep
kuldeep on 22 Sep 2024
Edited: Shubham on 22 Sep 2024
I am reading the header file as
header_file = 'C:\preprocessed\header.hdr';
info = enviinfo(header_file);
disp(info);
map_info = info.MapInfo;
disp(map_info);
ProjType: "UTM"
PixelTiePoints: [14186 1.0802e+04]
MapTiePoints: [4.3450e+05 2.0048e+06]
PixelSize: [10 10]
ProjZone: 43
NorthOrSouth: "North"
Datum: "World Geodetic System 1984"
Units: "Meters"
but I want to get it as follows
map info = {UTM,14186.0,10802.5,434499.57858948375,2004780.07582265,10.0,10.0,43,North,World Geodetic System 1984,units=Meters}
please suggest me how to get it as mentioned above.
kuldeep

Answers (1)

Shubham
Shubham on 22 Sep 2024
Hey Kuldeep,
In order to convert objects into a structure, simply use the "struct" function in MATLAB: https://www.mathworks.com/help/matlab/ref/struct.html#d126e1734438
s = struct(obj)
However, based on your query, I think you wish to store the information in the form of a cell array. For converting a struct into a cell array, pass it as an input parameter to the function "struct2cell": https://www.mathworks.com/help/matlab/ref/struct2cell.html
Happy coding!
  3 Comments
Umar
Umar on 22 Sep 2024

Hi @Kuldeep,

In order to achieve the desired output, you need to construct a formatted string that encapsulates various pieces of map information. Here is a breakdown of the code:

Variable Definitions

Start by defining individual variables for each piece of information we want to include in our output. This includes the UTM type, several numerical values, directional information, and the datum.

Using sprintf

The sprintf function is employed to format the string. This function allows us to create a string with specific formatting options. The placeholders within the string (e.g., %s, %.1f, %.15f, %d) are replaced by the corresponding variable values. %s is used for strings,%.1f for floating-point numbers with one decimal place,%.15f for floating-point numbers with fifteen decimal places,%d for integers.

Displaying the Output

Finally, use disp to print the formatted string to the console. This will show the output exactly as specified in the requirement. By executing this code, you will obtain the desired output, formatted precisely as requested.

Here is the refined code below which can be customized based on your later needs.

% Define the map information
utm = 'UTM';
value1 = 14186.0;
value2 = 10802.5;
value3 = 434499.57858948375;
value4 = 2004780.07582265;
value5 = 10.0;
value6 = 10.0;
value7 = 43;
direction = 'North';
datum = 'World Geodetic System 1984';
units = 'units=Meters';
% Create the formatted output
map_info = sprintf('map info =   
{%s,%.1f,%.1f,%.15f,%.15f,%.1f,%.1f,%d,%s,%s,%s}', ...
                 utm, value1, value2, value3, value4, value5,   
value6, value7, direction, datum, units);
% Display the output
disp(map_info);

Please see attached.

Please let me know if you have any further questions.

Shubham
Shubham on 22 Sep 2024
Edited: Shubham on 22 Sep 2024
Hey Kuldeep,
  • For getting the desired result, you can create a custom function which extracts each property from the class. You can use the sprintf method as mentioned by Umar, but instead of using "Value1", "Value2" etc, use the actual fields, for eg: "map_info.ProjType", "map_info.PixelTiePoints", etc.
  • Otherwise the cell array that you have already constructed using "struct2cell", you can just loop over the terms and form a separate array/cell array as you need. If the values are numeric or string, append them in "map_info2"(new array), otherwise use a nested loop/do this recursively.
I would recommend the second method as it would be more generalised.

Sign in to comment.

Products


Release

R2024a

Community Treasure Hunt

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

Start Hunting!