KMPlot

Survival times are data that measure follow-up time from a defined starting point to the occurrence of a given event, for example the time from the beginning to the end of a remission period or the time from the diagnosis of a disease to death. Standard statistical techniques cannot usually be applied because the underlying distribution is rarely Normal and the data are often ‘censored’. A survival time is described as censored when there is a follow-up time but the event has not yet occurred or is not known to have occurred. For example, if remission time is being studied and the patient is still in remission at the end of the study, then that patient’s remission time would be censored. If a patient for some reason drops out of a study before the end of the study period, then that patient’s follow-up time would also be considered to be
censored. The survival function S(t) is defined as the probability of surviving at least to time t. The graph of S(t) against t is called the survival curve. The Kaplan–Meier method can be used to estimate this curve from the observed survival times without the assumption of an underlying probability distribution. This function uses the vectorization technique.

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help section change to correctly cite this file; median time computation was changed (in some cases there is not median time)

The function was adapted to be recalled by LOGRANK function (a function of mine). More vectorization.

error correction in confidence curve trimming

improvement for censored data

Changes in description

Hazard rate computation added

function for hazard rate computation was changed to avoid NaN in non linear fit.
Now is possible to choose how to plot censored data: if spreades along period or at period of observation.

fixed a bug into "input error handling" section