NIFTI1_INTENT_CODES
NIFTI1_DATATYPES » NIFTI1_DATATYPE_ALIASES

nifti1 intent codes, to describe intended meaning of dataset contents More...

Collaboration diagram for NIFTI1_INTENT_CODES:

## Topics

| NIFTI1_XFORM_CODES
| nifti1 xform codes to describe the "standard" coordinate system

## Variables

const int32_t | cifti::NIFTI_INTENT_CORREL =2
const int32_t | cifti::NIFTI_INTENT_TTEST =3
const int32_t | cifti::NIFTI_INTENT_FTEST =4
const int32_t | cifti::NIFTI_INTENT_ZSCORE =5
const int32_t | cifti::NIFTI_INTENT_CHISQ =6
const int32_t | cifti::NIFTI_INTENT_BETA =7
const int32_t | cifti::NIFTI_INTENT_BINOM =8
const int32_t | cifti::NIFTI_INTENT_GAMMA =9
const int32_t | cifti::NIFTI_INTENT_POISSON =10
const int32_t | cifti::NIFTI_INTENT_NORMAL =11
const int32_t | cifti::NIFTI_INTENT_FTEST_NONC =12
const int32_t | cifti::NIFTI_INTENT_CHISQ_NONC =13
const int32_t | cifti::NIFTI_INTENT_LOGISTIC =14
const int32_t | cifti::NIFTI_INTENT_LAPLACE =15
const int32_t | cifti::NIFTI_INTENT_UNIFORM =16
const int32_t | cifti::NIFTI_INTENT_TTEST_NONC =17
const int32_t | cifti::NIFTI_INTENT_WEIBULL =18
const int32_t | cifti::NIFTI_INTENT_CHI =19
const int32_t | cifti::NIFTI_INTENT_INVGAUSS =20
const int32_t | cifti::NIFTI_INTENT_EXTVAL =21
const int32_t | cifti::NIFTI_INTENT_PVAL =22
const int32_t | cifti::NIFTI_INTENT_LOGPVAL =23
const int32_t | cifti::NIFTI_INTENT_LOG10PVAL =24
const int32_t | cifti::NIFTI_FIRST_STATCODE =2
const int32_t | cifti::NIFTI_LAST_STATCODE =24
const int32_t | cifti::NIFTI_INTENT_ESTIMATE =1001
const int32_t | cifti::NIFTI_INTENT_LABEL =1002
const int32_t | cifti::NIFTI_INTENT_NEURONAME =1003
const int32_t | cifti::NIFTI_INTENT_GENMATRIX =1004
const int32_t | cifti::NIFTI_INTENT_SYMMATRIX =1005
const int32_t | cifti::NIFTI_INTENT_DISPVECT =1006
const int32_t | cifti::NIFTI_INTENT_VECTOR =1007
const int32_t | cifti::NIFTI_INTENT_POINTSET =1008
const int32_t | cifti::NIFTI_INTENT_TRIANGLE =1009
const int32_t | cifti::NIFTI_INTENT_QUATERNION =1010
const int32_t | cifti::NIFTI_INTENT_DIMLESS =1011

## Detailed Description

nifti1 intent codes, to describe intended meaning of dataset contents

[C2, chap 32] Correlation coefficient R (1 param): p1 = degrees of freedom R/sqrt(1-R*R) is t-distributed with p1 DOF.

## Variable Documentation

## NIFTI_FIRST_STATCODE

const int32_t cifti::NIFTI_FIRST_STATCODE =2

Smallest intent_code that indicates a statistic.

## NIFTI_INTENT_BETA

const int32_t cifti::NIFTI_INTENT_BETA =7

[C2, chap 25] Beta distribution (2 params): p1=a, p2=b. Density(x) proportional to x^(a-1) * (1-x)^(b-1).

## NIFTI_INTENT_BINOM

const int32_t cifti::NIFTI_INTENT_BINOM =8

[U, chap 3] Binomial distribution (2 params): p1 = number of trials, p2 = probability per trial. Prob(x) = (p1 choose x) * p2^x * (1-p2)^(p1-x), for x=0,1,...,p1.

## NIFTI_INTENT_CHI

const int32_t cifti::NIFTI_INTENT_CHI =19

[C1, chap 18] Chi distribution (1 param): p1 = DOF. Density(x) proportional to x^(p1-1) * exp(-x^2/2) for x > 0. p1 = 1 = 'half normal' distribution p1 = 2 = Rayleigh distribution p1 = 3 = Maxwell-Boltzmann distribution.

## NIFTI_INTENT_CHISQ

const int32_t cifti::NIFTI_INTENT_CHISQ =6

[C1, chap 18] Chi-squared (1 param): p1 = DOF. Density(x) proportional to exp(-x/2) * x^(p1/2-1).

## NIFTI_INTENT_CHISQ_NONC

const int32_t cifti::NIFTI_INTENT_CHISQ_NONC =13

[C2, chap 29] Noncentral chi-squared statistic (2 params): p1 = DOF, p2 = noncentrality parameter.

## NIFTI_INTENT_DIMLESS

const int32_t cifti::NIFTI_INTENT_DIMLESS =1011

Dimensionless value - no params - although, as in _ESTIMATE the name of the parameter may be stored in intent_name.

## NIFTI_INTENT_DISPVECT

const int32_t cifti::NIFTI_INTENT_DISPVECT =1006

To signify that the vector value at each voxel is to be taken as a displacement field or vector:

- dataset must have a 5th dimension
- intent_code must be NIFTI_INTENT_DISPVECT
- dim[5] must be the dimensionality of the displacment vector (e.g., 3 for spatial displacement, 2 for in-plane)

## NIFTI_INTENT_ESTIMATE

const int32_t cifti::NIFTI_INTENT_ESTIMATE =1001

To signify that the value at each voxel is an estimate of some parameter, set intent_code = NIFTI_INTENT_ESTIMATE. The name of the parameter may be stored in intent_name.

## NIFTI_INTENT_EXTVAL

const int32_t cifti::NIFTI_INTENT_EXTVAL =21

[C2, chap 22] Extreme value type I (2 params): p1 = location, p2 = scale cdf(x) = exp(-exp(-(x-p1)/p2)).

## NIFTI_INTENT_FTEST

const int32_t cifti::NIFTI_INTENT_FTEST =4

[C2, chap 27] Fisher F statistic (2 params): p1 = numerator DOF, p2 = denominator DOF.

## NIFTI_INTENT_FTEST_NONC

const int32_t cifti::NIFTI_INTENT_FTEST_NONC =12

[C2, chap 30] Noncentral F statistic (3 params): p1 = numerator DOF, p2 = denominator DOF, p3 = numerator noncentrality parameter.

## NIFTI_INTENT_GAMMA

const int32_t cifti::NIFTI_INTENT_GAMMA =9

[C1, chap 17] Gamma distribution (2 params): p1 = shape, p2 = scale. Density(x) proportional to x^(p1-1) * exp(-p2*x).

## NIFTI_INTENT_GENMATRIX

const int32_t cifti::NIFTI_INTENT_GENMATRIX =1004

To store an M x N matrix at each voxel:

- dataset must have a 5th dimension (dim[0]=5 and dim[5]>1)
- intent_code must be NIFTI_INTENT_GENMATRIX
- dim[5] must be M*N
- intent_p1 must be M (in float format)
- intent_p2 must be N (ditto)
- the matrix values A[i][[j] are stored in row-order:
  - A[0][0] A[0][1] ... A[0][N-1]
  - A[1][0] A[1][1] ... A[1][N-1]
  - etc., until
  - A[M-1][0] A[M-1][1] ... A[M-1][N-1]

## NIFTI_INTENT_INVGAUSS

const int32_t cifti::NIFTI_INTENT_INVGAUSS =20

[C1, chap 15] Inverse Gaussian (2 params): p1 = mu, p2 = lambda Density(x) proportional to exp(-p2*(x-p1)^2/(2*p1^2*x)) / x^3 for x > 0.

## NIFTI_INTENT_LABEL

const int32_t cifti::NIFTI_INTENT_LABEL =1002

To signify that the value at each voxel is an index into some set of labels, set intent_code = NIFTI_INTENT_LABEL. The filename with the labels may stored in aux_file.

## NIFTI_INTENT_LAPLACE

const int32_t cifti::NIFTI_INTENT_LAPLACE =15

[C2, chap 24] Laplace distribution (2 params): p1 = location, p2 = scale. Density(x) proportional to exp(-abs(x-p1)/p2).

## NIFTI_INTENT_LOG10PVAL

const int32_t cifti::NIFTI_INTENT_LOG10PVAL =24

Data is log10(p-value) (no params). To be safe, a program should compute p = pow(10.,-abs(this_value)). The nifti_stats.c library returns this_value as positive, so that this_value = -log10(p).

## NIFTI_INTENT_LOGISTIC

const int32_t cifti::NIFTI_INTENT_LOGISTIC =14

[C2, chap 23] Logistic distribution (2 params): p1 = location, p2 = scale. Density(x) proportional to sech^2((x-p1)/(2*p2)).

## NIFTI_INTENT_LOGPVAL

const int32_t cifti::NIFTI_INTENT_LOGPVAL =23

Data is ln(p-value) (no params). To be safe, a program should compute p = exp(-abs(this_value)). The nifti_stats.c library returns this_value as positive, so that this_value = -log(p).

## NIFTI_INTENT_NEURONAME

const int32_t cifti::NIFTI_INTENT_NEURONAME =1003

To signify that the value at each voxel is an index into the NeuroNames labels set, set intent_code = NIFTI_INTENT_NEURONAME.

## NIFTI_INTENT_NORMAL

const int32_t cifti::NIFTI_INTENT_NORMAL =11

[C1, chap 13] Normal distribution (2 params): p1 = mean, p2 = standard deviation.

## NIFTI_INTENT_POINTSET

const int32_t cifti::NIFTI_INTENT_POINTSET =1008

To signify that the vector value at each voxel is really a spatial coordinate (e.g., the vertices or nodes of a surface mesh):

- dataset must have a 5th dimension
- intent_code must be NIFTI_INTENT_POINTSET
- dim[0] = 5
- dim[1] = number of points
- dim[2] = dim[3] = dim[4] = 1
- dim[5] must be the dimensionality of space (e.g., 3 => 3D space).
- intent_name may describe the object these points come from (e.g., "pial", "gray/white" , "EEG", "MEG").

## NIFTI_INTENT_POISSON

const int32_t cifti::NIFTI_INTENT_POISSON =10

[U, chap 4] Poisson distribution (1 param): p1 = mean. Prob(x) = exp(-p1) * p1^x / x! , for x=0,1,2,....

## NIFTI_INTENT_PVAL

const int32_t cifti::NIFTI_INTENT_PVAL =22

Data is a 'p-value' (no params).

## NIFTI_INTENT_QUATERNION

const int32_t cifti::NIFTI_INTENT_QUATERNION =1010

To signify that the vector value at each voxel is a quaternion:

- dataset must have a 5th dimension
- intent_code must be NIFTI_INTENT_QUATERNION
- dim[0] = 5
- dim[5] = 4
- datatype should be a floating point type

## NIFTI_INTENT_SYMMATRIX

const int32_t cifti::NIFTI_INTENT_SYMMATRIX =1005

To store an NxN symmetric matrix at each voxel:

- dataset must have a 5th dimension
- intent_code must be NIFTI_INTENT_SYMMATRIX
- dim[5] must be N*(N+1)/2
- intent_p1 must be N (in float format)
- the matrix values A[i][[j] are stored in row-order:
  - A[0][0]
  - A[1][0] A[1][1]
  - A[2][0] A[2][1] A[2][2]
  - etc.: row-by-row

## NIFTI_INTENT_TRIANGLE

const int32_t cifti::NIFTI_INTENT_TRIANGLE =1009

To signify that the vector value at each voxel is really a triple of indexes (e.g., forming a triangle) from a pointset dataset:

- dataset must have a 5th dimension
- intent_code must be NIFTI_INTENT_TRIANGLE
- dim[0] = 5
- dim[1] = number of triangles
- dim[2] = dim[3] = dim[4] = 1
- dim[5] = 3
- datatype should be an integer type (preferably DT_INT32)
- the data values are indexes (0,1,...) into a pointset dataset.

## NIFTI_INTENT_TTEST

const int32_t cifti::NIFTI_INTENT_TTEST =3

[C2, chap 28] Student t statistic (1 param): p1 = DOF.

## NIFTI_INTENT_TTEST_NONC

const int32_t cifti::NIFTI_INTENT_TTEST_NONC =17

[C2, chap 31] Noncentral t statistic (2 params): p1 = DOF, p2 = noncentrality parameter.

## NIFTI_INTENT_UNIFORM

const int32_t cifti::NIFTI_INTENT_UNIFORM =16

[C2, chap 26] Uniform distribution: p1 = lower end, p2 = upper end.

## NIFTI_INTENT_WEIBULL

const int32_t cifti::NIFTI_INTENT_WEIBULL =18

[C1, chap 21] Weibull distribution (3 params): p1 = location, p2 = scale, p3 = power. Density(x) proportional to ((x-p1)/p2)^(p3-1) * exp(-((x-p1)/p2)^p3) for x > p1.

## NIFTI_INTENT_ZSCORE

const int32_t cifti::NIFTI_INTENT_ZSCORE =5

[C1, chap 13] Standard normal (0 params): Density = N(0,1).

## NIFTI_LAST_STATCODE

const int32_t cifti::NIFTI_LAST_STATCODE =24

Largest intent_code that indicates a statistic.