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| | *It is used to model the lifetime of technical devices and is used to describe the particle size distribution of particles generated by grinding, milling and crushing operations. | | *It is used to model the lifetime of technical devices and is used to describe the particle size distribution of particles generated by grinding, milling and crushing operations. |
| | *This distribution is closely related to the lognormal distribution. | | *This distribution is closely related to the lognormal distribution. |
| − | *In WEIBULL(x,alpha,beta,lv),x is the value to evaluate the function. | + | *In <math>WEIBULL(x,alpha,beta,lv)</math>,<math> x </math> is the value to evaluate the function. |
| − | *alpha is the shape parameter of the distribution.beta is the scale parameter of the distribution. | + | *<math> alpha </math> is the shape parameter of the distribution.<math> beta </math> is the scale parameter of the distribution. |
| − | *lv is the logical value which determines the form of the distribution. | + | *<math>lv</math> is the logical value which determines the form of the distribution. |
| − | *When lv is TRUE, this function gives the value of the cumulative distribution. When lv is FALSE, then this function gives the value of the probability density function. | + | *When <math>lv</math> is TRUE, this function gives the value of the cumulative distribution. When <math>lv</math> is FALSE, then this function gives the value of the probability density function. |
| − | *When we are not omitting the value of lv, then it consider as FALSE. | + | *When we are not omitting the value of <math>lv</math>, then it consider as FALSE. |
| | *Weibull distribution is of two type :3-parameter weibull distribution and 2-parameter weibull distribution. | | *Weibull distribution is of two type :3-parameter weibull distribution and 2-parameter weibull distribution. |
| | *This function gives the value of 2-parameter weibull distribution by setting the third parameter (location parameter) is zero. | | *This function gives the value of 2-parameter weibull distribution by setting the third parameter (location parameter) is zero. |
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| | *If alpha=1, then the failure rate of the device is constant over time. | | *If alpha=1, then the failure rate of the device is constant over time. |
| | *If alpha>1, then the failure rate of the device increases over time. | | *If alpha>1, then the failure rate of the device increases over time. |
| − | *The equation for cumulative distribution function is: <math>F(x,\alpha,\beta) = 1-e^{-(\frac{x}{\beta})}^\alpha</math>. | + | *The equation for cumulative distribution function is: <math>F(x,\alpha,\beta) = 1-e^-{(\frac{x}{β})}^α</math> |
| | *The equation for probability density function is: | | *The equation for probability density function is: |
| − | <math>f(x,\alpha,\beta) = \frac{\alpha}{\beta^\alpha}.x^{\alpha-1}.e^{-(\frac{x}{\beta})}^\alpha.</math> | + | <math>f(x,\alpha,\beta) = \frac{\alpha}{\beta^\alpha}.x^{\alpha-1}.e^-{(\frac{x}{\beta})}^\alpha.</math> |
| − | *When alpha =1, then this function gives the exponentail with λ=1/β. | + | *When alpha =1, then this function gives the exponentail with <math>\lambda=\frac{1}{\beta}</math>. |
| | *This function gives the result as error when | | *This function gives the result as error when |
| | 1. Any one of the argument is non-numeric. | | 1. Any one of the argument is non-numeric. |