Popular Functions in IML
Posted on Jan 02, 2015 in Computer Science
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** Things under legendu.net/outdated are outdated technologies that the author does not plan to update any more. Please look for better alternatives. **
dif
: lagged difference, keep missing values, may or may not what you want,
can use negative lag,
always return a matrix, with columns corresponding to differences of specified lags
if only 1 lag is specified, return a matrix with 1 column.
lag
: the usage is similar to dif
the dif<n>
and lag<n>
are for the data steps
loc
equivalence of which
in R
j
repeat
REPEAT Function
Returns a character value that consists of the first argument repeated n+1 times.
colvec rowvec
shape
SHAPE Function
SHAPE (matrix, nrow <, ncol> <, pad-value> ) ;
The SHAPE function reshapes and repeats values in a matrix.
choose
, kind of like ifelse
in R
cuSum
cuProd
diag
sample
(x <, n> <, method> <, prob> ) ;
ssq
shape
for numeric
cshape
for character
concat
like paste in R
change
like replace
qntl
Call for sample quantile
quantile
corr
standard
var
mean
mod
EXPANDGRID Function EXPANDGRID (x1, x2 <, x3> …<, x15>) ; The EXPANDGRID function is part of the IMLMLIB library. The arguments to the EXPANDGRID function are \(k\) vectors, \(2 \leq k \leq 15\). The EXPANDGRID function returns a matrix that contains the Cartesian product of elements from the specified vectors. If the \(i\)th argument has \(n_ i\) elements, the return matrix has \(\Pi _{i\leq k}n_ i\) rows and \(k\) columns.
ROWVEC Function ROWVEC (matrix) ;
SHAPECOL Function SHAPECOL (matrix, nrow <, ncol> <, pad-value> ) ; The SHAPECOL function reshapes and repeats values in a matrix. It is similar to the SHAPE function except that the SHAPECOL function produces the result matrix by traversing the argument matrix in column-major order.
String
strip works both in the data step and the iml procedure