Besides the system-provided functions, esProc supports invoking user-defined functions to handle some special operations or the encapsulation of certain computations. This article will briefly explain how to invoke user-defined functions with invoke function and how to use parameters and return the results as needed.
2015-02-27 152 0
Unconventional statistical tasks are not uncommon during report creation, but they are difficult if handled solely by a reporting tool like Jasper or BIRT, or SQL. For example it is troublesome to display result of dynamically relating a master report to its corresponding subreports existing in multiple databases. Yet ...
2015-02-26 187 0
1. esProc’s function options
Many functions in esProc can use function options with which the same function can have different work patterns. The basic format of function options is f@o(…) in which o is f function’s option. For example:
2015-02-18 190 0
Parallel computing solves a computational problem by breaking it apart into discrete subtasks and distributing them among multiple servers on which they will be implemented concurrently. Each subtask returns its own computational result to the master task for combination. Through the simultaneous use of multiple comput...
2015-02-17 380 0
Sequential computation was the simplest and most intuitive processing method for handling computational tasks. Contemporary servers and PCs, however, have gained the multi-tasking ability with multi-core CPUs. Under the circumstances, sequential computation cannot make the most use of the computational power the CPU of...
2015-02-16 209 0
Unconventional statistical tasks are not uncommon in creating reports with reporting tools like Jasper and BIRT. One of the cases is to display the result of certain comparisons between the current record and the next/previous record. It is difficult to handle it using only the reporting tool or the SQL. Yet esProc can...
2015-02-13 202 0
Unconventional statistical tasks are difficult to be handled solely by the reporting tool like Jasper and BIRT, or the SQL. For example when the original data are not arranged as required by the tabular report, they need to be transposed for display. However, with the assistance of esProc that has a powerful computing ...
2015-02-12 188 0
To make data analysis, first you need to load the original data. The data used most frequently comes from the text files or the databases. In esProc, you can load data from the text files or the databases easily and quickly.
1. Text file data
esProc can loaddata from a text file as a table sequence. For example, the te...
2015-02-11 233 0
esProc provides a large number of functions, many of which use many parameters. In order to clearly judge the positions of these parameters and make writing and reading easier, esProc is specially equipped with multilayer separators of function parameters.
1. Separators of function parameters
Colon (:), comma (,) and s...
2015-02-10 192 0
It’s difficult to handle unconventional statistical tasks using simply the reporting tool, like Jasper or BIRT, or SQL. One of the cases is that the source data don’t meet the crosstab’s requirements and thus need to be transposed for display. Having powerful computing engine to process structured data and being integr...
2015-02-09 222 0
In the article esProc External Memory Computing: Concept of Cursor, we only touched on the basic usage of the cross-cellset cursor. Here we’ll delve into more issues about it.
1. Basic usage
The cross-cellset cursor is typically used to handle big data analysis and computing, but it doesn’t impose a minimum limit on da...
2015-02-06 224 0
Since sets are commonly used in esProc, the latter provides comprehensive set operations.
1. Binary Operation on Sets
The most basic set in esProc is sequence. Let’s look at some basic binary operations between two sequences A and B.
Concatenation: Concatenate the two sequences straightforwardly. The members of B...
2015-02-05 138 0
Sometimes you are required to sort the detailed data in a spreadsheet. However, the sorting is difficult to realize due to the inflexible operation in Excel. You have to sort the data by groups, which requires quite a lot of work.
But you can perform the operation more easily in esCalc. Let’s look at an example. Summar...
2015-02-04 119 0
In an esProc table sequence, a single or multiple fields can be used as a primary key. We can make query based on the primary key using some special functions, which can both simplify the code and increase computational performance effectively.
1. find and pfind
Primary keys are common used in database tables. The valu...
2015-02-04 213 0
The esProc table sequence is a structured two-dimensional table, having concepts of field, record, primary key and reference. These concepts originate from the data table of relational database. A table sequence is also an explicit set of genericity and orderliness, which can perform structured data computing more flex...
2015-02-03 190 0