Developer Reference

Contents

v?ExpInt1

Computes the exponential integral of vector elements.

Syntax

vsExpInt1
(
n
,
a
,
y
)
;
vsExpInt1I(n, a, inca, y, incy);
vmsExpInt1
(
n
,
a
,
y
,
mode
)
;
vmsExpInt1I(n, a, inca, y, incy, mode);
vdExpInt1
(
n
,
a
,
y
)
;
vdExpInt1I(n, a, inca, y, incy);
vmdExpInt1
(
n
,
a
,
y
,
mode
)
;
vmdExpInt1I(n, a, inca, y, incy, mode);
Include Files
  • mkl.h
Input Parameters
Name
Type
Description
n
const MKL_INT
Specifies the number of elements to be calculated.
a
const float*
for
vsExpInt1
,
vmsExpInt1
const double*
for
vdExpInt1
,
vmdExpInt1
Pointer to an array that contains the input vector
a
.
inca
,
incy
const MKL_INT
Specifies increments for the elements of
a
and
y
.
mode
const MKL_INT64
Overrides global VM mode setting for this function call. See
vmlSetMode
for possible values and their description.
Output Parameters
Name
Type
Description
y
float*
for
vsExpInt1
,
vmsExpInt1
double*
for
vdExpInt1
,
vmdExpInt1
Pointer to an array that contains the output vector
y
.
Description
The
v?ExpInt1
function computes the exponential integral
E
1
of vector elements.
For positive real values
x
, this can be written as:
.
For negative real values
x
, the result is defined as
NAN
.
Special Values for Real Function
v?ExpInt1(x)
Argument
Result
VM Error Status
Exception
x
< +0
QNAN
VML_STATUS_ERRDOM
INVALID
+0
+
VML_STATUS_SING
ZERODIVIDE
-0
+
VML_STATUS_SING
ZERODIVIDE
+
+0
 
 
-
QNAN
VML_STATUS_ERRDOM
INVALID
QNAN
QNAN
 
 
SNAN
QNAN
 
INVALID

Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.