---
name: "dlascl.f"
section: "3"
platform: "linux"
package: "lapack-doc"
version: "3.12.1-2"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/dlascl.f"
---

# dlascl.f(3)

## NAME

SRC/dlascl.f

## SYNOPSIS

### Functions/Subroutines

subroutine **dlascl** (type, kl, ku, cfrom, cto, m, n, a, lda, info)\
 **DLASCL** multiplies a general rectangular matrix by a real scalar defined as cto/cfrom.

## Function/Subroutine Documentation

### subroutine dlascl (character type, integer kl, integer ku, double precision cfrom, double precision cto, integer m, integer n, double precision, dimension( lda, \* ) a, integer lda, integer info)

**DLASCL** multiplies a general rectangular matrix by a real scalar defined as cto/cfrom.

**Purpose:**

```
!>
!> DLASCL multiplies the M by N real matrix A by the real scalar
!> CTO/CFROM.  This is done without over/underflow as long as the final
!> result CTO*A(I,J)/CFROM does not over/underflow. TYPE specifies that
!> A may be full, upper triangular, lower triangular, upper Hessenberg,
!> or banded.
!>
```

**Parameters**

*TYPE*

```
!>          TYPE is CHARACTER*1
!>          TYPE indices the storage type of the input matrix.
!>          = 'G':  A is a full matrix.
!>          = 'L':  A is a lower triangular matrix.
!>          = 'U':  A is an upper triangular matrix.
!>          = 'H':  A is an upper Hessenberg matrix.
!>          = 'B':  A is a symmetric band matrix with lower bandwidth KL
!>                  and upper bandwidth KU and with the only the lower
!>                  half stored.
!>          = 'Q':  A is a symmetric band matrix with lower bandwidth KL
!>                  and upper bandwidth KU and with the only the upper
!>                  half stored.
!>          = 'Z':  A is a band matrix with lower bandwidth KL and upper
!>                  bandwidth KU. See DGBTRF for storage details.
!>
```

*KL*

```
!>          KL is INTEGER
!>          The lower bandwidth of A.  Referenced only if TYPE = 'B',
!>          'Q' or 'Z'.
!>
```

*KU*

```
!>          KU is INTEGER
!>          The upper bandwidth of A.  Referenced only if TYPE = 'B',
!>          'Q' or 'Z'.
!>
```

*CFROM*

```
!>          CFROM is DOUBLE PRECISION
!>
```

*CTO*

```
!>          CTO is DOUBLE PRECISION
!>
!>          The matrix A is multiplied by CTO/CFROM. A(I,J) is computed
!>          without over/underflow if the final result CTO*A(I,J)/CFROM
!>          can be represented without over/underflow.  CFROM must be
!>          nonzero.
!>
```

*M*

```
!>          M is INTEGER
!>          The number of rows of the matrix A.  M >= 0.
!>
```

*N*

```
!>          N is INTEGER
!>          The number of columns of the matrix A.  N >= 0.
!>
```

*A*

```
!>          A is DOUBLE PRECISION array, dimension (LDA,N)
!>          The matrix to be multiplied by CTO/CFROM.  See TYPE for the
!>          storage type.
!>
```

*LDA*

```
!>          LDA is INTEGER
!>          The leading dimension of the array A.
!>          If TYPE = 'G', 'L', 'U', 'H', LDA >= max(1,M);
!>             TYPE = 'B', LDA >= KL+1;
!>             TYPE = 'Q', LDA >= KU+1;
!>             TYPE = 'Z', LDA >= 2*KL+KU+1.
!>
```

*INFO*

```
!>          INFO is INTEGER
!>          0  - successful exit
!>          <0 - if INFO = -i, the i-th argument had an illegal value.
!>
```

**Author**

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Definition at line **142** of file **dlascl.f**.

## Author

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