| Headings - part 2 |
| Part of the "Working With QuSheet" tutorial for QuSheet |
| Part of the "Working With QuSheet" tutorial for QuSheet |
| Summary |
Headings are not called simply “calculations” because they do not, generally speaking, have to make calculations at all – they can simply be used in the normal sense of the word “heading” with sub-headings placed below them (for example the Leaflet Quick Win scenario). Calculation in a Heading is an option. |
Styles control everything about how a Heading’s output is displayed. Indeed every Heading entry has a column to specify the Style that should be used for the entry. Styles are treated in more detail in later tutorials. |
Where a Heading is making a calculation, the Heading keeps a running-total to allow a calculation to take place. Starting with an undefined value, each line in a Heading has an operation to modify this running total into either a number, a Boolean (true/false) value or text. When necessary, an "undefined" value is promoted to a suitable value (like 0 if you start adding numbers up) accordingy. |
The first column in a Heading line, the “Apply” column, specifies the operation to be performed on the running total. The Operand of the operation, where necessary, is given in the “On” column. |
QuSheet does its calculations like a calculator – i.e, not taking into account operator precedence, simply performing one operation after another (e.g. 10 + 10 * 10 comes to 200, not 110). |
The “Set” operation sets the running total to the value of the operand |
The “Ignore” operation leaves the running total alone |
A: The Igrnore operation also now supports an operand which is undefined – i.e. not found – by silently ignoring the whole line. |
Mathematical operations (plus, minus and so on) perform a maths operation between the running total and the operand, setting the result into the running total. |
A: The + and – operations work with text, by causing an “append” or “prepend” of the operand, promoting either running-total or operand to text if necessary first. |
Formatted text operations are used to construct text with embedded formatting. |
A: It is now possible to pre-pend formatted text ( -: ) |
Comparison operations produce a Boolean (yes/no) value. |
The “if true then” and “if false then” operations set the running total to the operand if the current running total is true or false respectively. |
| Summary » |
| View (duration 11m10s) |
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| Addenda / Errata |
A: The Igrnore operation also now supports an operand which is undefined – i.e. not found – by silently ignoring the whole line. |
A: The + and – operations work with text, by causing an “append” or “prepend” of the operand, promoting either running-total or operand to text if necessary first. |
A: It is now possible to pre-pend formatted text ( -: ) |
| Addenda / Errata » |
| « Summary |
Headings are not called simply “calculations” because they do not, generally speaking, have to make calculations at all – they can simply be used in the normal sense of the word “heading” with sub-headings placed below them (for example the Leaflet Quick Win scenario). Calculation in a Heading is an option. |
Styles control everything about how a Heading’s output is displayed. Indeed every Heading entry has a column to specify the Style that should be used for the entry. Styles are treated in more detail in later tutorials. |
Where a Heading is making a calculation, the Heading keeps a running-total to allow a calculation to take place. Starting with an undefined value, each line in a Heading has an operation to modify this running total into either a number, a Boolean (true/false) value or text. When necessary, an "undefined" value is promoted to a suitable value (like 0 if you start adding numbers up) accordingy. |
The first column in a Heading line, the “Apply” column, specifies the operation to be performed on the running total. The Operand of the operation, where necessary, is given in the “On” column. |
QuSheet does its calculations like a calculator – i.e, not taking into account operator precedence, simply performing one operation after another (e.g. 10 + 10 * 10 comes to 200, not 110). |
The “Set” operation sets the running total to the value of the operand |
The “Ignore” operation leaves the running total alone |
A: The Igrnore operation also now supports an operand which is undefined – i.e. not found – by silently ignoring the whole line. |
Mathematical operations (plus, minus and so on) perform a maths operation between the running total and the operand, setting the result into the running total. |
A: The + and – operations work with text, by causing an “append” or “prepend” of the operand, promoting either running-total or operand to text if necessary first. |
Formatted text operations are used to construct text with embedded formatting. |
A: It is now possible to pre-pend formatted text ( -: ) |
Comparison operations produce a Boolean (yes/no) value. |
The “if true then” and “if false then” operations set the running total to the operand if the current running total is true or false respectively. |
| « Addenda / Errata |
A: The Igrnore operation also now supports an operand which is undefined – i.e. not found – by silently ignoring the whole line. |
A: The + and – operations work with text, by causing an “append” or “prepend” of the operand, promoting either running-total or operand to text if necessary first. |
A: It is now possible to pre-pend formatted text ( -: ) |
-> output produced by QuSheet, licenced to "Richard Develyn", 15 Oct 2009 130|1|24094