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General applied math

abs Returns the absolute value of numeric data.
acos Computes the inverse cosine of numeric types.
asin Computes the inverse sine of numeric types.
atan Computes the inverse tangent of numeric types.
atan2 Computes the inverse tangent of (y/x) for numeric types.
avg Computes the average of a variable regardless of dimensionality.
betainc Evaluates the incomplete beta function.
bw_bandpass_filter Applies a Butterworth bandpass filter optimized for narrow bandwidths to time series.
calculate_daily_values Calculate daily values [avg, sum, min, max] from high frequency temporal values.
calculate_monthly_values Calculate monthly values [avg, sum, min, max] from high frequency temporal values.
calculate_segment_values Calculate segment (eg, pentad [5-day], weekly [7-day]) values from high frequency temporal values.
cancor Performs canonical correlation analysis between two sets of variables.
cdft_p Calculates the one-sided probability given a t-value and the degrees of freedom.
cdft_t Calculates the t-value given the one-sided probability and the degrees of freedom.
ceemdan Complete Ensemble Empirical Mode Decomposition with Adaptive Noise.
ceil Returns the smallest integral value greater than or equal to each input value.
center_finite_diff Performs a centered finite difference operation on the rightmost dimension.
center_finite_diff_n Performs a centered finite difference operation on the given dimension.
cfftb Performs a backward complex discrete fourier transform [Fourier Synthesis].
cfftf Performs a forward complex discrete fourier transform of a real periodic sequence.
cfftf_frq_reorder Reorders the data returned by cfftf.
chiinv Evaluates the inverse chi-squared distribution function.
cohsq_c2p Given coherence-squared and the effective degrees-of-freedom, calculate the associated probability.
cohsq_p2c Calculate the value(s) of coherence-squared required for a specified significance level and effectiove degrees-of-freedom.
cos Computes the cosine of numeric types.
cosh Computes the hyperbolic cosine of numeric types.
covcorm Calculates a covariance or correlation matrix.
covcorm_xy Calculates a covariance or correlation matrix given two separate 'n x m' arrays.
cumsum Calculates the cumulative sum.
decimalPlaces Truncates or rounds to the number of decimal places specified.
demod_cmplx Perform a complex demodulation on one or more time series.
determinant Calculates the determinant of a square real matrix.
dim_acumrun_n Calculates individual accumulated sums of sequences ('runs') of a specified length.
dim_avg Computes the average of a variable's rightmost dimension at all other dimensions.
dim_avg_n Computes the average of a variable's given dimension(s) at all other dimensions.
dim_avg_n_Wrap Computes the average of a variable's given dimensions at all other dimensions and retains metadata.
dim_avg_wgt Computes the weighted average of a variable's rightmost dimension at all other dimensions.
dim_avg_wgt_n Computes the weighted average of a variable's given dimension at all other dimensions.
dim_avg_wgt_n_Wrap Computes the weighted average of a variable's given dimension at all other dimensions and retains metadata.
dim_avg_wgt_Wrap Computes the weighted average of a variable's rightmost dimension at all other dimensions and retains metadata.
dim_avg_Wrap Computes the average of a variable's rightmost dimension at all other dimensions and retains metadata.
dim_cumsum Calculates the cumulative sum along the rightmost dimension.
dim_cumsum_n Calculates the cumulative sum along the given dimension(s).
dim_cumsum_n_Wrap Calculates the cumulative sum along the given dimension(s) and retains metadata.
dim_cumsum_Wrap Calculates the cumulative sum along the rightmost dimension and retains metadata.
dim_max Finds the maximum of a variable's rightmost dimension at all other dimensions.
dim_max_n Finds the maximum of a variable's given dimensions at all other dimensions.
dim_max_n_Wrap Computes the maximum of a variable's given dimensions at all other dimensions and retains metadata.
dim_median Computes the median of a variable's rightmost dimension at all other dimensions.
dim_median_n Computes the median of a variable's given dimensions at all other dimensions.
dim_min Finds the minimum of a variable's rightmost dimension at all other dimensions.
dim_min_n Finds the minimum of a variable's given dimensions at all other dimensions.
dim_min_n_Wrap Computes the minimum of a variable's given dimensions at all other dimensions and retains metadata.
dim_num Calculates the number of True values of a variable's rightmost dimension at all other dimensions.
dim_num_n Calculates the number of True values of a variable's given dimensions at all other dimensions.
dim_numrun_n Counts the number of "runs" (sequences) within a series containing zeros and ones.
dim_pqsort Computes the permutation vector generated by sorting the n - 1th (rightmost) dimension.
dim_pqsort_n Computes the permutation vector generated by sorting the given dimension.
dim_product Computes the product of a variable's rightmost dimension at all other dimensions.
dim_product_n Computes the product of a variable's given dimension(s) at all other dimensions.
dim_rmsd Computes the root-mean-square-difference between two variables' rightmost dimension at all other dimensions.
dim_rmsd_n Computes the root-mean-square-difference between two variables' given dimensions at all other dimensions.
dim_rmsd_n_Wrap Computes the root-mean-square-difference between two variables' given dimensions at all other dimensions.
dim_rmsd_Wrap Computes the root-mean-square-difference between two variables' rightmost dimension at all other dimensions.
dim_rmvmean Calculates and removes the mean of the (rightmost) dimension at all other dimensions.
dim_rmvmean_n Calculates and removes the mean of the given dimension(s) at all other dimensions.
dim_rmvmean_n_Wrap Calculates and removes the mean of the given dimensions at all other dimensions and retains metadata.
dim_rmvmean_Wrap Calculates and removes the mean of the (rightmost) dimension at all other dimensions and retains metadata.
dim_rmvmed Calculates and removes the median of the (rightmost) dimension at all other dimensions.
dim_rmvmed_n Calculates and removes the median of the given dimension(s) at all other dimensions.
dim_rmvmed_n_Wrap Calculates and removes the median of the given dimensions at all other dimensions and retains metadata.
dim_rmvmed_Wrap Calculates and removes the median of the (rightmost) dimension at all other dimensions and retains metadata.
dim_standardize Calculates standardized anomalies of the rightmost dimension at all other dimensions.
dim_standardize_n Calculates standardized anomalies of the given dimension(s) at all other dimensions.
dim_standardize_n_Wrap Calculates standardized anomalies of the given dimensions at all other dimensions and retains metadata.
dim_standardize_Wrap Calculates standardized anomalies of the rightmost dimension at all other dimensions and retains metadata.
dim_stat4 Computes the first four moments (average, sample variance, skewness, and kurtosis) of the rightmost dimension for all other dimensions.
dim_stat4_n Computes the first four moments (average, sample variance, skewness, and kurtosis) of the given dimension(s) for all other dimensions.
dim_stddev Computes the sample standard deviation of a variable's rightmost dimension at all other dimensions.
dim_stddev_n Computes the sample standard deviation of a variable's given dimension(s) at all other dimensions.
dim_stddev_n_Wrap Computes the sample standard deviation of a variable's given dimension(s) at all other dimensions and retains metadata.
dim_stddev_Wrap Computes the sample standard deviation of a variable's rightmost dimension at all other dimensions and retains metadata.
dim_sum Computes the arithmetic sum of a variable's rightmost dimension at all other dimensions.
dim_sum_n Computes the arithmetic sum of a variable's given dimension(s) at all other dimensions.
dim_sum_n_Wrap Computes the arithmetic sum of a variable's given dimensions at all other dimensions and retains metadata.
dim_sum_wgt Computes the weighted sum of a variable's rightmost dimension at all other dimensions.
dim_sum_wgt_n Computes the weighted sum of a variable's given dimension at all other dimensions.
dim_sum_wgt_n_Wrap Computes the weighted sum of a variable's given dimension at all other dimensions and retains metadata.
dim_sum_wgt_Wrap Computes the weighted sum of a variable's rightmost dimension at all other dimensions and retains metadata.
dim_sum_Wrap Computes the arithmetic sum of a variable's rightmost dimension at all other dimensions and retains metadata.
dim_variance Computes the unbiased estimates of the variance of a variable's rightmost dimension.
dim_variance_n Computes the unbiased estimates of the variance of a variable's given dimension(s) at all other dimensions.
dim_variance_n_Wrap Computes unbiased estimates of the variance of a variable's given dimension(s) at all other dimensions and retains metadata.
dim_variance_Wrap Computes unbiased estimates of the variance of a variable's rightmost dimension at all other dimensions and retains metadata.
dtrend Estimates and removes the least squares linear trend of the rightmost dimension from all grid points.
dtrend_leftdim Estimates and removes the least squares linear trend of the leftmost dimension from all grid points and retains metadata.
dtrend_msg Estimates and removes the least squares linear trend of the rightmost dimension from all grid points (missing values allowed).
dtrend_msg_n Estimates and removes the least squares linear trend of the dim-th dimension from all grid points (missing values allowed).
dtrend_n Estimates and removes the least squares linear trend of the given dimension from all grid points.
dtrend_quadratic Estimates and removes the least squares quadratic trend of the rightmost dimension from all grid points.
dtrend_quadratic_msg_n Estimates and removes the least squares quadratic trend of the dim-th dimension from all grid points (missing values allowed).
eemd Perform ensemble empirical mode decomposition (EEMD).
equiv_sample_size Estimates the number of independent values of a series of correlated observations.
erf Evaluates the real error function.
erfc Evaluates the real complementary error function.
esacr Computes sample auto-correlations.
esacv Computes sample auto-covariances
esccr Computes sample cross-correlations.
esccv Computes sample cross-covariances.
escorc Computes the (Pearson) sample linear cross-correlations at lag 0 only.
escorc_n Computes the (Pearson) sample linear cross-correlations at lag 0 only, across the specified dimensions.
escovc Computes sample cross-covariances at lag 0 only.
exp Computes the value of e (the base of natural logarithms) raised to the power of the input.
exponential_curve_fit Calculates the coefficients for a simple exponential curve fit of the form ' y = A*exp(B*x)' using least squares.
ezfftb Perform a Fourier synthesis from real and imaginary coefficients.
ezfftb_n Perform a Fourier synthesis from real and imaginary coefficients on the given dimension.
ezfftf Perform a Fourier analysis on a real periodic sequence.
ezfftf_n Performs a Fourier analysis on a real periodic sequence on the given dimension.
fabs Computes the absolute value of numeric types.
fft2db Performs a two-dimensional discrete backward Fourier transform (Fourier synthesis).
fft2df Performs a two-dimensional forward real discrete Fourier transform (i.e., Fourier analysis) of a real periodic array.
fftshift Rearranges an array in a manner similar to Matlab's fftshift function.
filwgts_lancos Calculates one-dimensional filter weights (deprecated).
filwgts_lanczos Calculates one-dimensional filter weights.
filwgts_normal Calculates one-dimensional filter weights based upon the normal (gaussian) distribution.
floor Returns the largest integral value less than or equal to each input value.
fourier_info Performs Fourier analysis on one or more periodic series.
ftest Applies F-test for variances and returns an estimate of the statistical significance.
gamma Evaluates the complete gamma function.
gammainc Evaluates the incomplete gamma function.
genNormalDist Generates a normal distribution.
get_d2r Return a constant that converts degrees to radians.
get_pi Return pi as a type float or double.
get_r2d Return a constant that converts radians to degrees.
inverse_matrix Computes the inverse of a general matrix using LU factorization.
kde Uses gaussian kernel density estimation (KDE) to estimate the probability density function of a random variable. This function is under construction and is available for testing only. It may not be released with NCL V6.5.0.
kf_filter Extract equatorial waves by filtering in the Wheeler-Kiladis wavenumber-frequency domain.
kmeans_as136 Performs k-means clustering via the Hartigan and Wong AS-136 algorithm.
kolsm2_n Uses the Kolmogorov-Smirnov two-sample test to determine if two samples are from the same distribution.
kron_product Computes the Kronecker product for two-dimensional matrices.
linrood_latwgt Computes the latitudes and weights used by the Lin-Rood Model.
linrood_wgt Computes the weights used by the Lin-Rood Model.
local_max Determines the relative maxima for a 2-dimensional array.
local_min Determines the relative minima for a 2-dimensional array.
log Computes the natural log of a numeric type.
log10 Computes the log base 10 of a numeric type.
lspoly Calculates a set of coefficients for a weighted least squares polynomial fit to the given data.
lspoly_n Calculates a set of coefficients for a weighted least squares polynomial fit to the given data on the given dimension.
max Computes the maximum value of a multi-dimensional array.
min Computes the minimum value of a multi-dimensional array.
mod Remainder function which emulates the Fortran "mod" intrinsic function.
NewCosWeight Performs cosine of the latitude weighting on the given array.
pattern_cor Compute centered or uncentered pattern correlation.
pdfx Generates a univariate probability density distribution (PDF).
pdfxy Generates a joint probability density distribution. (Please use pdfxy_conform.)
pdfxy_bin Performs looping necessary to calculate the bivariate (joint) probability distribution (see pdfxy).
pdfxy_conform An interface to pdfxy that allows the input arrays to be different sizes.
product Computes the product of the input.
qsort Sorts a singly dimensioned array.
quadroots Determine roots of a quadratic equation [ a*x^2 + b*x + c].
reg_multlin Performs basic multiple linear regression analysis.
reg_multlin_stats Performs multiple linear regression analysis including confidence estimates and creates an ANOVA table.
regcoef Calculates the linear regression coefficient between two variables.
regCoef Calculates the linear regression coefficient between two variables.
regCoef_n Calculates the linear regression coefficient between two variables on the given dimensions.
regline Calculates the linear regression coefficient between two series.
regline_stats Performs simple linear regression including confidence estimates, an ANOVA table and 95% mean response estimates.
regline_weight Calculates the linear regression coefficient between two series where the dependent (y) variable's values are weighted by some measure of uncertainty (typically, standard deviations) such that the Chi-square goodness-of-fit is minimized.
rmInsufData Sets all instances (i.e., time) of a grid point to missing if a user-prescribed percentage of points is missing.
round Rounds a float or double variable to the nearest whole number.
run_cor Calculates a running correlation.
runave Calculates an unweighted running average on the rightmost dimension.
runave_n Calculates an unweighted running average on the given dimension.
runave_n_Wrap Calculates an unweighted running average on the given dimension and retains metadata.
runave_Wrap Calculates an unweighted running average on the rightmost dimension and retains metadata.
sign_f90 Mimic the behavior of Fortran-90's sign transfer function.
sign_matlab Mimic the behavior of Matlab's sign function.
simpeq Integrate a sequence of equally spaced points using Simpson's Rule.
simpne Integrates a sequence of unequally or equally spaced points using Simpson's three-point formula.
sin Computes the sine of numeric types.
sindex_yrmo Calculates the Southern Oscillation Index given two series of year-month values.
sinh Computes the hyperbolic sine of numeric types.
smth9 Performs nine point local smoothing on one or more 2D grids.
smth9_Wrap Performs nine point local smoothing on one or more 2D grids and retains metadata.
snindex_yrmo Calculates the Southern Oscillation Index and the noise index given two series of year-month values.
solve_linsys Computes the solution to a real system of linear equations.
sparse_matrix_mult Multiplies a sparse matrix with a dense matrix.
spcorr Computes Spearman rank order correlation (Rho) correlation coefficient.
spcorr_n Computes Spearman rank order correlation (Rho) correlation coefficient across the given dimension.
specx_anal Calculates spectra of a series.
specx_ci Calculates the theoretical Markov spectrum and the lower and upper confidence curves.
specxy_anal Calculates cross spectra quantities of a series.
sqrt Computes the square root of its input.
SqrtCosWeight Performs square-root of the cosine of the latitude weighting on the given array.
sqsort Sorts a singly dimensioned arrays of strings.
stat2 Calculates the first two moments of the given input.
stat4 Calculates estimates of the first four moments (mean, variance, skewness, and kurtosis) of the given input.
stat_dispersion Computes a number of robust statistics.
stat_medrng Calculates median, range, and mid-range of the given input.
stat_trim Calculates trimmed estimates of the first two moments of the given input.
stddev Calculates the sample standard deviation.
student_t Calculates the two-tailed probability of the Student-t distribution.
sum Sums the input.
tan Computes the tangent of numeric types.
tanh Computes the hyperbolic tangent of numeric types.
taper Applies split-cosine-bell tapering to one or more series across the rightmost dimension.
taper_n Applies split-cosine-bell tapering to one or more series across the given dimension.
taylor_stats Calculates statistics needed for the Taylor Diagram: pattern_correlation, ratio and bias.
trend_manken Calculates Mann-Kendall non-parametric test for monotonic trend and the Theil-Sen robust estimate of linear trend.
ttest Returns an estimate of the statistical significance and, optionally, the t-values.
variance Computes an unbiased estimate the variance of all input points.
wave_number_spc Computes the total power spectrum as a function of latitudinal wave number.
wavelet Calculates the wavelet transform of a time series and significance levels.
wavelet_default Calculates the wavelet transform of a time series and significance levels.
weibull Derives the shape and scale parameters for the Weibull distribution via maximum likelihood estimates.
wgt_area_smooth Smooths an array of data using a 5-point 2D area-weighted smoothing algorithm.
wgt_areaave Calculates the area average of a quantity using weights.
wgt_areaave2 Calculates the area average of a quantity using two-dimensional weights.
wgt_areaave_Wrap Calculates the area average of a quantity using weights and retains metadata.
wgt_arearmse Calculates a weighted area root-mean-square-difference between two variables.
wgt_arearmse2 Calculates a weighted area root-mean-square-difference (rmse) between two variables using two-dimensional weights.
wgt_areasum2 Calculates the area sum (total) of a quantity using two-dimensional weights.
wgt_runave Calculates a weighted running average across the rightmost dimension.
wgt_runave_leftdim Calculate a weighted running average over the leftmost dimension (usually, "time") and return in the original order with metadata.
wgt_runave_n Calculates a weighted running average across the given dimension.
wgt_runave_n_Wrap Calculates a weighted running average on the given dimension and retains metadata.
wgt_runave_Wrap Calculates a weighted running average on the rightmost dimension and retains metadata.
wgt_volave Calculates the volume average of a quantity using weights.
wgt_volave_ccm Calculates the volume average of a quantity from the CCM using weights.
wgt_volrmse Calculates a weighted volume root-mean-square-difference between two variables.
wgt_volrmse_ccm Calculates a weighted volume root-mean-square-difference between two variables from the CCM.
wk_smooth121 Performs a specialized 1-2-1 filter for Wheeler-Kiladis plots.
zonalAve Computes a zonal average of the input array.