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ee.Array.firstNonZero

Page Summary

Array.firstNonZero(right) is a method that returns an Array.
This method selects the first value on an element-wise basis if it is non-zero and the second value otherwise.
It takes two Array arguments: left (the left-hand value) and right (the right-hand value).

On an element-wise basis, selects the first value if it is non-zero, and the second value otherwise.

Usage	Returns
`Array. firstNonZero (right)`	Array

Argument	Type	Details
this: `left`	Array	The left-hand value.
`right`	Array	The right-hand value.

Examples

Code Editor (JavaScript)

 var 
  
 empty 
  
 = 
  
 ee 
 . 
 Array 
 ([], 
  
 ee 
 . 
 PixelType 
 . 
 int8 
 ()); 
 print 
 ( 
 empty 
 . 
 firstNonZero 
 ( 
 empty 
 )); 
  
 // [] 
 print 
 ( 
 ee 
 . 
 Array 
 ([ 
 0 
 ]). 
 firstNonZero 
 ( 
 0 
 )); 
  
 // [0] 
 print 
 ( 
 ee 
 . 
 Array 
 ([ 
 0 
 ]). 
 firstNonZero 
 ([ 
 0 
 ])); 
  
 // [0] 
 print 
 ( 
 ee 
 . 
 Array 
 ([ 
 0 
 ]). 
 firstNonZero 
 ([ 
 1 
 ])); 
  
 // [1] 
 print 
 ( 
 ee 
 . 
 Array 
 ([ 
 2 
 ]). 
 firstNonZero 
 ([ 
 3 
 ])); 
  
 // [2] 
 print 
 ( 
 ee 
 . 
 Array 
 ([ 
 1 
 ]). 
 firstNonZero 
 ([ 
 0 
 ])); 
  
 // [1] 
 print 
 ( 
 ee 
 . 
 Array 
 ([ 
 - 
 1 
 , 
  
 0 
 , 
  
 1 
 ]). 
 firstNonZero 
 ([ 
 2 
 , 
  
 - 
 1 
 , 
  
 2 
 ])); 
  
 // [-1,-1,1] 
 // [[1,2],[3,4]] 
 print 
 ( 
 ee 
 . 
 Array 
 ([[ 
 1 
 , 
  
 2 
 ], 
  
 [ 
 0 
 , 
  
 0 
 ]]). 
 firstNonZero 
 ([[ 
 0 
 , 
  
 0 
 ], 
  
 [ 
 3 
 , 
  
 4 
 ]]));

Python setup

See the Python Environment page for information on the Python API and using geemap for interactive development.

 import 
  
 ee 
 import 
  
 geemap.core 
  
 as 
  
 geemap

Colab (Python)

 empty 
 = 
 ee 
 . 
 Array 
 ([], 
 ee 
 . 
 PixelType 
 . 
 int8 
 ()) 
 display 
 ( 
 empty 
 . 
 firstNonZero 
 ( 
 empty 
 )) 
 # [] 
 display 
 ( 
 ee 
 . 
 Array 
 ([ 
 0 
 ]) 
 . 
 firstNonZero 
 ( 
 0 
 )) 
 # [0] 
 display 
 ( 
 ee 
 . 
 Array 
 ([ 
 0 
 ]) 
 . 
 firstNonZero 
 ([ 
 0 
 ])) 
 # [0] 
 display 
 ( 
 ee 
 . 
 Array 
 ([ 
 0 
 ]) 
 . 
 firstNonZero 
 ([ 
 1 
 ])) 
 # [1] 
 display 
 ( 
 ee 
 . 
 Array 
 ([ 
 2 
 ]) 
 . 
 firstNonZero 
 ([ 
 3 
 ])) 
 # [2] 
 display 
 ( 
 ee 
 . 
 Array 
 ([ 
 1 
 ]) 
 . 
 firstNonZero 
 ([ 
 0 
 ])) 
 # [1] 
 display 
 ( 
 ee 
 . 
 Array 
 ([ 
 - 
 1 
 , 
 0 
 , 
 1 
 ]) 
 . 
 firstNonZero 
 ([ 
 2 
 , 
 - 
 1 
 , 
 2 
 ])) 
 # [-1, -1, 1] 
 # [[1, 2], [3, 4]] 
 display 
 ( 
 ee 
 . 
 Array 
 ([[ 
 1 
 , 
 2 
 ], 
 [ 
 0 
 , 
 0 
 ]]) 
 . 
 firstNonZero 
 ([[ 
 0 
 , 
 0 
 ], 
 [ 
 3 
 , 
 4 
 ]]))

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Page Summary

Examples

Code Editor (JavaScript)

Colab (Python)

ee.Array.firstNonZero