MIN(3) 1 MIN(3)
min - Find lowest value
SYNOPSIS
mixed min (array $values)
DESCRIPTION
mixed min (mixed $value1, mixed $value2, [mixed $...])
If the first and only parameter is an array, min(3) returns the lowest value in that array. If at least two parameters are provided,
min(3) returns the smallest of these values.
Note
Values of different types will be compared using the standard comparison rules. For instance, a non-numeric string will be com-
pared to an integer as though it were 0, but multiple string values will be compared alphanumerically. The actual value returned
will be of the original type with no conversion applied.
PARAMETERS
o $values
- An array containing the values.
o $value1
- Any comparable value.
o $value2
- Any comparable value.
o $...
- Any comparable value.
RETURN VALUES
min(3) returns the parameter value considered "lowest" according to standard comparisons. If multiple values of different types evaluate as
equal (e.g. 0 and 'abc') the first provided to the function will be returned.
EXAMPLES
Example #1
Example uses of min(3)
<?php
echo min(2, 3, 1, 6, 7); // 1
echo min(array(2, 4, 5)); // 2
// The string 'hello' when compared to an int is treated as 0
// Since the two values are equal, the order they are provided determines the result
echo min(0, 'hello'); // 0
echo min('hello', 0); // hello
// Here we are comparing -1 < 0, so -1 is the lowest value
echo min('hello', -1); // -1
// With multiple arrays of different lengths, min returns the shortest
$val = min(array(2, 2, 2), array(1, 1, 1, 1)); // array(2, 2, 2)
// Multiple arrays of the same length are compared from left to right
// so in our example: 2 == 2, but 4 < 5
$val = min(array(2, 4, 8), array(2, 5, 1)); // array(2, 4, 8)
// If both an array and non-array are given, the array is never returned
// as comparisons treat arrays as greater than any other value
$val = min('string', array(2, 5, 7), 42); // string
// If one argument is NULL or a boolean, it will be compared against
// other values using the rule FALSE < TRUE regardless of the other types involved
// In the below examples, both -10 and 10 are treated as TRUE in the comparison
$val = min(-10, FALSE, 10); // FALSE
$val = min(-10, NULL, 10); // NULL
// 0, on the other hand, is treated as FALSE, so is "lower than" TRUE
$val = min(0, TRUE); // 0
?>
SEE ALSO
max(3), count(3).
PHP Documentation Group MIN(3)
Check Out this Related Man Page
CGESVD(l) ) CGESVD(l)
NAME
CGESVD - compute the singular value decomposition (SVD) of a complex M-by-N matrix A, optionally computing the left and/or right singular
vectors
SYNOPSIS
SUBROUTINE CGESVD( JOBU, JOBVT, M, N, A, LDA, S, U, LDU, VT, LDVT, WORK, LWORK, RWORK, INFO )
CHARACTER JOBU, JOBVT
INTEGER INFO, LDA, LDU, LDVT, LWORK, M, N
REAL RWORK( * ), S( * )
COMPLEX A( LDA, * ), U( LDU, * ), VT( LDVT, * ), WORK( * )
PURPOSE
CGESVD computes the singular value decomposition (SVD) of a complex M-by-N matrix A, optionally computing the left and/or right singular
vectors. The SVD is written
A = U * SIGMA * conjugate-transpose(V)
where SIGMA is an M-by-N matrix which is zero except for its min(m,n) diagonal elements, U is an M-by-M unitary matrix, and V is an N-by-N
unitary matrix. The diagonal elements of SIGMA are the singular values of A; they are real and non-negative, and are returned in descend-
ing order. The first min(m,n) columns of U and V are the left and right singular vectors of A.
Note that the routine returns V**H, not V.
ARGUMENTS
JOBU (input) CHARACTER*1
Specifies options for computing all or part of the matrix U:
= 'A': all M columns of U are returned in array U:
= 'S': the first min(m,n) columns of U (the left singular vectors) are returned in the array U; = 'O': the first min(m,n) columns
of U (the left singular vectors) are overwritten on the array A; = 'N': no columns of U (no left singular vectors) are computed.
JOBVT (input) CHARACTER*1
Specifies options for computing all or part of the matrix V**H:
= 'A': all N rows of V**H are returned in the array VT;
= 'S': the first min(m,n) rows of V**H (the right singular vectors) are returned in the array VT; = 'O': the first min(m,n) rows
of V**H (the right singular vectors) are overwritten on the array A; = 'N': no rows of V**H (no right singular vectors) are com-
puted.
JOBVT and JOBU cannot both be 'O'.
M (input) INTEGER
The number of rows of the input matrix A. M >= 0.
N (input) INTEGER
The number of columns of the input matrix A. N >= 0.
A (input/output) COMPLEX array, dimension (LDA,N)
On entry, the M-by-N matrix A. On exit, if JOBU = 'O', A is overwritten with the first min(m,n) columns of U (the left singular
vectors, stored columnwise); if JOBVT = 'O', A is overwritten with the first min(m,n) rows of V**H (the right singular vectors,
stored rowwise); if JOBU .ne. 'O' and JOBVT .ne. 'O', the contents of A are destroyed.
LDA (input) INTEGER
The leading dimension of the array A. LDA >= max(1,M).
S (output) REAL array, dimension (min(M,N))
The singular values of A, sorted so that S(i) >= S(i+1).
U (output) COMPLEX array, dimension (LDU,UCOL)
(LDU,M) if JOBU = 'A' or (LDU,min(M,N)) if JOBU = 'S'. If JOBU = 'A', U contains the M-by-M unitary matrix U; if JOBU = 'S', U
contains the first min(m,n) columns of U (the left singular vectors, stored columnwise); if JOBU = 'N' or 'O', U is not referenced.
LDU (input) INTEGER
The leading dimension of the array U. LDU >= 1; if JOBU = 'S' or 'A', LDU >= M.
VT (output) COMPLEX array, dimension (LDVT,N)
If JOBVT = 'A', VT contains the N-by-N unitary matrix V**H; if JOBVT = 'S', VT contains the first min(m,n) rows of V**H (the right
singular vectors, stored rowwise); if JOBVT = 'N' or 'O', VT is not referenced.
LDVT (input) INTEGER
The leading dimension of the array VT. LDVT >= 1; if JOBVT = 'A', LDVT >= N; if JOBVT = 'S', LDVT >= min(M,N).
WORK (workspace/output) COMPLEX array, dimension (LWORK)
On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
LWORK (input) INTEGER
The dimension of the array WORK. LWORK >= 1. LWORK >= 2*MIN(M,N)+MAX(M,N). For good performance, LWORK should generally be
larger.
If LWORK = -1, then a workspace query is assumed; the routine only calculates the optimal size of the WORK array, returns this
value as the first entry of the WORK array, and no error message related to LWORK is issued by XERBLA.
RWORK (workspace) REAL array, dimension (5*min(M,N))
On exit, if INFO > 0, RWORK(1:MIN(M,N)-1) contains the unconverged superdiagonal elements of an upper bidiagonal matrix B whose
diagonal is in S (not necessarily sorted). B satisfies A = U * B * VT, so it has the same singular values as A, and singular vec-
tors related by U and VT.
INFO (output) INTEGER
= 0: successful exit.
< 0: if INFO = -i, the i-th argument had an illegal value.
> 0: if CBDSQR did not converge, INFO specifies how many superdiagonals of an intermediate bidiagonal form B did not converge to
zero. See the description of RWORK above for details.
LAPACK version 3.0 15 June 2000 CGESVD(l)