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PlaneshifterPlaneshifter
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Add logcdf and logpdf to constructor
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‎lib/node_modules/@stdlib/math/base/dist/exponential/ctor/README.md‎

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@@ -171,6 +171,28 @@ var y = exponential.cdf( 0.5 );
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// returns ~0.632
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```
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#### Exponential.prototype.logcdf( x )
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Evaluates the natural logarithm of the [cumulative distribution function][cdf] (CDF).
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```javascript
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var exponential = new Exponential( 2.0 );
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var y = exponential.logcdf( 0.5 );
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// returns ~-0.459
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```
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#### Exponential.prototype.logpdf( x )
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Evaluates the natural logarithm of the [probability density function][pdf] (PDF).
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```javascript
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var exponential = new Exponential( 2.0 );
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var y = exponential.logpdf( 0.8 );
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// returns ~-0.906
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```
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#### Exponential.prototype.mgf( t )
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Evaluates the [moment-generating function][mgf] (MGF).

‎lib/node_modules/@stdlib/math/base/dist/exponential/ctor/docs/repl.txt‎

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@@ -42,6 +42,14 @@
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exponential.cdf: Function
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Evaluates the cumulative distribution function (CDF).
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exponential.logcdf: Function
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Evaluates the natural logarithm of the cumulative distribution function
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(CDF).
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exponential.logpdf: Function
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Evaluates the natural logarithm of the probability density function
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(PDF).
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exponential.mgf: Function
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Evaluates the moment-generating function (MGF).
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@@ -74,6 +82,10 @@
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~0.028
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> exponential.cdf( 1.0 )
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~0.998
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> exponential.logcdf( 1.0 )
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~-0.002
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> exponential.logpdf( 1.5 )
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~-6.908
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> exponential.mgf( -0.5 )
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~0.923
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> exponential.pdf( 1.5 )

‎lib/node_modules/@stdlib/math/base/dist/exponential/ctor/lib/ctor.js‎

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@@ -14,6 +14,8 @@ var skewness = require( '@stdlib/math/base/dist/exponential/skewness' );
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var stdev = require( '@stdlib/math/base/dist/exponential/stdev' );
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var variance = require( '@stdlib/math/base/dist/exponential/variance' );
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var cdf = require( '@stdlib/math/base/dist/exponential/cdf' );
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var logcdf = require( '@stdlib/math/base/dist/exponential/logcdf' );
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var logpdf = require( '@stdlib/math/base/dist/exponential/logpdf' );
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var mgf = require( '@stdlib/math/base/dist/exponential/mgf' );
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var pdf = require( '@stdlib/math/base/dist/exponential/pdf' );
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var quantile = require( '@stdlib/math/base/dist/exponential/quantile' );
@@ -32,6 +34,28 @@ function exponentialCDF( x ) {
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return cdf( x, this.lambda );
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} // end FUNCTION exponentialCDF()
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/**
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* Evaluates the natural logarithm of the cumulative distribution function (CDF).
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*
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* @private
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* @param {number} x - input value
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* @returns {number} evaluated logCDF
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*/
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function exponentialLogCDF( x ) {
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return logcdf( x, this.lambda );
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} // end FUNCTION exponentialLogCDF()
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/**
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* Evaluates the natural logarithm of the probability density function (PDF).
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*
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* @private
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* @param {number} x - input value
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* @returns {number} evaluated logPDF
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*/
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function exponentialLogPDF( x ) {
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return logpdf( x, this.lambda );
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} // end FUNCTION exponentialLogPDF()
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/**
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* Evaluates the moment-generating function (MGF).
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*
@@ -311,6 +335,42 @@ Object.defineProperty( Exponential.prototype, 'variance', {
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*/
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setReadOnly( Exponential.prototype, 'cdf', exponentialCDF );
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/**
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* Evaluates the natural logarithm of the cumulative distribution function (CDF).
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*
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* @memberof Exponential.prototype
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* @name logcdf
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* @type {Function}
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* @param {number} x - input value
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* @returns {number} evaluated logCDF
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* @see [cdf]{@link https://en.wikipedia.org/wiki/Cumulative_distribution_function}
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*
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* @example
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* var exponential = new Exponential( 2.0 );
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*
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* var v = exponential.logcdf( 0.5 );
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* // returns ~-0.459
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*/
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setReadOnly( Exponential.prototype, 'logcdf', exponentialLogCDF );
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/**
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* Evaluates the natural logarithm of the probability density function (PDF).
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*
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* @memberof Exponential.prototype
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* @name logpdf
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* @type {Function}
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* @param {number} x - input value
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* @returns {number} evaluated logPDF
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* @see [pdf]{@link https://en.wikipedia.org/wiki/Probability_density_function}
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*
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* @example
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* var exponential = new Exponential( 2.0 );
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*
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* var v = exponential.logpdf( 0.8 );
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* // returns ~-0.906
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*/
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setReadOnly( Exponential.prototype, 'logpdf', exponentialLogPDF );
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/**
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* Evaluates the moment-generating function (MGF).
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*

‎lib/node_modules/@stdlib/math/base/dist/exponential/ctor/test/test.js‎

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@@ -7,6 +7,8 @@ var isFunction = require( '@stdlib/assert/is-function' );
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var hasOwnProp = require( '@stdlib/assert/has-own-property' );
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var quantile = require( '@stdlib/math/base/dist/exponential/quantile' );
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var cdf = require( '@stdlib/math/base/dist/exponential/cdf' );
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var logcdf = require( '@stdlib/math/base/dist/exponential/logcdf' );
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var logpdf = require( '@stdlib/math/base/dist/exponential/logpdf' );
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var mgf = require( '@stdlib/math/base/dist/exponential/mgf' );
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var pdf = require( '@stdlib/math/base/dist/exponential/pdf' );
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var entropy = require( '@stdlib/math/base/dist/exponential/entropy' );
@@ -229,6 +231,34 @@ tape( 'the distribution prototype has a method for evaluating the cumulative dis
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t.end();
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});
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tape( 'the distribution prototype has a method for evaluating the natural logarithm of the cumulative distribution function (CDF)', function test( t ) {
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var exponential;
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var y;
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t.strictEqual( hasOwnProp( Exponential.prototype, 'logcdf' ), true, 'has property' );
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t.strictEqual( isFunction( Exponential.prototype.logcdf ), true, 'has method' );
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exponential = new Exponential();
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y = exponential.logcdf( 0.5 );
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t.strictEqual( y, logcdf( 0.5, 1.0 ), 'returns expected value' );
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t.end();
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});
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tape( 'the distribution prototype has a method for evaluating the natural logarithm of the probability density function (PDF)', function test( t ) {
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var exponential;
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var y;
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t.strictEqual( hasOwnProp( Exponential.prototype, 'logpdf' ), true, 'has property' );
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t.strictEqual( isFunction( Exponential.prototype.logpdf ), true, 'has method' );
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exponential = new Exponential();
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y = exponential.logpdf( 0.2 );
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t.strictEqual( y, logpdf( 0.2, 1.0 ), 'returns expected value' );
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t.end();
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});
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tape( 'the distribution prototype has a method for evaluating the moment-generating function (MGF)', function test( t ) {
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var exponential;
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var y;

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