# How to calculate the statistcs for extracted region?

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## How to calculate the statistcs for extracted region?

 I have a binary file(a) with size of (360 720 )for the globe.I wrote the code given below to read and extract an area (south america)from that file. when I use summary for the whole file I got: summary(a, na.rm=FALSE) Min. 1st Qu.  Median    Mean 3rd Qu.    Max.    NA's 0.00    1.00    3.00    4.15    7.00   20.00  200083 . But when I used summary for the region(b) which I extracted, I got many V1,V2, V3. Which is not right I should have got one line (as for a )not many V1,V2. Here is the code: X <- c(200:300) Y <- c(150:190) conne <- file("C:\\initial-WTD.bin", "rb") a=readBin(conne, numeric(), size=4,  n=360*720, signed=TRUE) a[a == -9999] <- NA y <- matrix(data=a,ncol=360,nrow=720) image(t(t(y[X,Y])),ylim=c(1,0)) b = y[X,Y] summary(b,na.rm=TRUE)    V1            V2            V3            V4            V5           V6            V7              Min.   : 1.000   Min.   : 1.000   Min.   : 1.000   Min.   : 1.000   Min.   : 0.000   Min.   : 0.000    1st Qu.: 4.000   1st Qu.: 4.000   1st Qu.: 4.000   1st Qu.: 3.000   1st Qu.: 2.000   1st Qu.: 2.000    Median : 5.000   Median : 6.000   Median : 5.000   Median : 5.000   Median : 5.000   Median : 5.000    Mean   : 5.808   Mean   : 5.962   Mean   : 5.506   Mean   : 4.946   Mean   : 5.068   Mean   : 4.829    3rd Qu.: 6.750   3rd Qu.: 7.000   3rd Qu.: 7.000   3rd Qu.: 6.000   3rd Qu.: 7.000   3rd Qu.: 6.000    Max.   :18.000   Max.   :19.000   Max.   :17.000   Max.   :13.000   Max.   :19.000   Max.   :18.000