docs: verify queries + operations docs against real execution

- queries-select: fix prose reference to removed cols: syntax
- queries-joins: left-join shows 0 for unmatched i64, not blank
- queries-pivot: fix avg output (149.5/152.0 not 149.5/152), replace
  broken select+scan/iasc window examples with standalone equivalents,
  fix grouped window to use by: Sym (not by: {Sym: Sym}) and cols: syntax
- operations-math: remove nonexistent abs/sqrt/drop, fix div output
  (3.0 not 3.333), round/floor/ceil return floats, booleans are
  true/false not 1b/0b, within takes (vec [lo hi]) not (x lo hi),
  take is (take vec n), xbar is (xbar vec n), filter takes mask not
  predicate fn, apply takes args directly, med returns float
- operations-string: remove nonexistent upper/lower/strlen/trim/substr/
  replace/ilike builtins (DAG-only), fix concat to binary, like uses
  glob wildcards (*/?) not SQL (%), format uses % placeholder not {}

Author: singaraiona

website/docs/operations-math.html

@@ -134,7 +134,7 @@ <h2 id="arithmetic">Arithmetic</h2>
           <span class="fn-type">atomic</span>
         </div>
         <div class="fn-desc">Division. Integer division for integer arguments, float division otherwise.</div>
-        <div class="fn-example">(<span class="hl-fn">/</span> <span class="hl-num">10</span> <span class="hl-num">3</span>)  <span class="hl-comment">; 3</span><br>(<span class="hl-fn">/</span> <span class="hl-num">10.0</span> <span class="hl-num">3</span>)  <span class="hl-comment">; 3.333...</span></div>
+        <div class="fn-example">(<span class="hl-fn">/</span> <span class="hl-num">10</span> <span class="hl-num">3</span>)  <span class="hl-comment">; 3</span><br>(<span class="hl-fn">/</span> <span class="hl-num">10.0</span> <span class="hl-num">3</span>)  <span class="hl-comment">; 3.0</span></div>
       </div>
 
       <div class="fn-card">
@@ -155,31 +155,13 @@ <h2 id="arithmetic">Arithmetic</h2>
         <div class="fn-example">(<span class="hl-fn">neg</span> <span class="hl-num">5</span>)  <span class="hl-comment">; -5</span><br>(<span class="hl-fn">neg</span> [<span class="hl-num">1</span> <span class="hl-num">-2</span> <span class="hl-num">3</span>])  <span class="hl-comment">; [-1 2 -3]</span></div>
       </div>
 
-      <div class="fn-card">
-        <div class="fn-card-header">
-          <span class="fn-name">(abs x)</span>
-          <span class="fn-type">atomic</span>
-        </div>
-        <div class="fn-desc">Absolute value.</div>
-        <div class="fn-example">(<span class="hl-fn">abs</span> <span class="hl-num">-7</span>)  <span class="hl-comment">; 7</span><br>(<span class="hl-fn">abs</span> [<span class="hl-num">-3</span> <span class="hl-num">0</span> <span class="hl-num">5</span>])  <span class="hl-comment">; [3 0 5]</span></div>
-      </div>
-
-      <div class="fn-card">
-        <div class="fn-card-header">
-          <span class="fn-name">(sqrt x)</span>
-          <span class="fn-type">atomic</span>
-        </div>
-        <div class="fn-desc">Square root. Returns float.</div>
-        <div class="fn-example">(<span class="hl-fn">sqrt</span> <span class="hl-num">16</span>)  <span class="hl-comment">; 4.0</span><br>(<span class="hl-fn">sqrt</span> [<span class="hl-num">4</span> <span class="hl-num">9</span> <span class="hl-num">25</span>])  <span class="hl-comment">; [2.0 3.0 5.0]</span></div>
-      </div>
-
       <div class="fn-card">
         <div class="fn-card-header">
           <span class="fn-name">(round x)</span>
           <span class="fn-type">atomic</span>
         </div>
         <div class="fn-desc">Round to nearest integer.</div>
-        <div class="fn-example">(<span class="hl-fn">round</span> <span class="hl-num">3.7</span>)  <span class="hl-comment">; 4</span><br>(<span class="hl-fn">round</span> [<span class="hl-num">1.2</span> <span class="hl-num">2.5</span> <span class="hl-num">3.8</span>])  <span class="hl-comment">; [1 3 4]</span></div>
+        <div class="fn-example">(<span class="hl-fn">round</span> <span class="hl-num">3.7</span>)  <span class="hl-comment">; 4.0</span><br>(<span class="hl-fn">round</span> [<span class="hl-num">1.2</span> <span class="hl-num">2.5</span> <span class="hl-num">3.8</span>])  <span class="hl-comment">; [1.0 3.0 4.0]</span></div>
       </div>
 
       <div class="fn-card">
@@ -188,7 +170,7 @@ <h2 id="arithmetic">Arithmetic</h2>
           <span class="fn-type">atomic</span>
         </div>
         <div class="fn-desc">Round down to nearest integer.</div>
-        <div class="fn-example">(<span class="hl-fn">floor</span> <span class="hl-num">3.9</span>)  <span class="hl-comment">; 3</span></div>
+        <div class="fn-example">(<span class="hl-fn">floor</span> <span class="hl-num">3.9</span>)  <span class="hl-comment">; 3.0</span></div>
       </div>
 
       <div class="fn-card">
@@ -197,7 +179,7 @@ <h2 id="arithmetic">Arithmetic</h2>
           <span class="fn-type">atomic</span>
         </div>
         <div class="fn-desc">Round up to nearest integer.</div>
-        <div class="fn-example">(<span class="hl-fn">ceil</span> <span class="hl-num">3.1</span>)  <span class="hl-comment">; 4</span></div>
+        <div class="fn-example">(<span class="hl-fn">ceil</span> <span class="hl-num">3.1</span>)  <span class="hl-comment">; 4.0</span></div>
       </div>
 
       <!-- ============================================================ -->
@@ -210,7 +192,7 @@ <h2 id="comparison">Comparison</h2>
           <span class="fn-type">atomic</span>
         </div>
         <div class="fn-desc">Equal. Works on all types including strings and symbols.</div>
-        <div class="fn-example">(<span class="hl-fn">==</span> <span class="hl-num">3</span> <span class="hl-num">3</span>)  <span class="hl-comment">; 1b</span><br>(<span class="hl-fn">==</span> [<span class="hl-num">1</span> <span class="hl-num">2</span> <span class="hl-num">3</span>] <span class="hl-num">2</span>)  <span class="hl-comment">; [0b 1b 0b]</span></div>
+        <div class="fn-example">(<span class="hl-fn">==</span> <span class="hl-num">3</span> <span class="hl-num">3</span>)  <span class="hl-comment">; true</span><br>(<span class="hl-fn">==</span> [<span class="hl-num">1</span> <span class="hl-num">2</span> <span class="hl-num">3</span>] <span class="hl-num">2</span>)  <span class="hl-comment">; [false true false]</span></div>
       </div>
 
       <div class="fn-card">
@@ -219,7 +201,7 @@ <h2 id="comparison">Comparison</h2>
           <span class="fn-type">atomic</span>
         </div>
         <div class="fn-desc">Not equal.</div>
-        <div class="fn-example">(<span class="hl-fn">!=</span> <span class="hl-num">3</span> <span class="hl-num">4</span>)  <span class="hl-comment">; 1b</span></div>
+        <div class="fn-example">(<span class="hl-fn">!=</span> <span class="hl-num">3</span> <span class="hl-num">4</span>)  <span class="hl-comment">; true</span></div>
       </div>
 
       <div class="fn-card">
@@ -228,7 +210,7 @@ <h2 id="comparison">Comparison</h2>
           <span class="fn-type">atomic</span>
         </div>
         <div class="fn-desc">Less than.</div>
-        <div class="fn-example">(<span class="hl-fn">&lt;</span> <span class="hl-num">3</span> <span class="hl-num">5</span>)  <span class="hl-comment">; 1b</span><br>(<span class="hl-fn">&lt;</span> [<span class="hl-num">1</span> <span class="hl-num">5</span> <span class="hl-num">3</span>] <span class="hl-num">4</span>)  <span class="hl-comment">; [1b 0b 1b]</span></div>
+        <div class="fn-example">(<span class="hl-fn">&lt;</span> <span class="hl-num">3</span> <span class="hl-num">5</span>)  <span class="hl-comment">; true</span><br>(<span class="hl-fn">&lt;</span> [<span class="hl-num">1</span> <span class="hl-num">5</span> <span class="hl-num">3</span>] <span class="hl-num">4</span>)  <span class="hl-comment">; [true false true]</span></div>
       </div>
 
       <div class="fn-card">
@@ -237,7 +219,7 @@ <h2 id="comparison">Comparison</h2>
           <span class="fn-type">atomic</span>
         </div>
         <div class="fn-desc">Less than or equal.</div>
-        <div class="fn-example">(<span class="hl-fn">&lt;=</span> <span class="hl-num">3</span> <span class="hl-num">3</span>)  <span class="hl-comment">; 1b</span></div>
+        <div class="fn-example">(<span class="hl-fn">&lt;=</span> <span class="hl-num">3</span> <span class="hl-num">3</span>)  <span class="hl-comment">; true</span></div>
       </div>
 
       <div class="fn-card">
@@ -246,7 +228,7 @@ <h2 id="comparison">Comparison</h2>
           <span class="fn-type">atomic</span>
         </div>
         <div class="fn-desc">Greater than.</div>
-        <div class="fn-example">(<span class="hl-fn">&gt;</span> <span class="hl-num">5</span> <span class="hl-num">3</span>)  <span class="hl-comment">; 1b</span></div>
+        <div class="fn-example">(<span class="hl-fn">&gt;</span> <span class="hl-num">5</span> <span class="hl-num">3</span>)  <span class="hl-comment">; true</span></div>
       </div>
 
       <div class="fn-card">
@@ -255,16 +237,15 @@ <h2 id="comparison">Comparison</h2>
           <span class="fn-type">atomic</span>
         </div>
         <div class="fn-desc">Greater than or equal.</div>
-        <div class="fn-example">(<span class="hl-fn">&gt;=</span> <span class="hl-num">5</span> <span class="hl-num">5</span>)  <span class="hl-comment">; 1b</span></div>
+        <div class="fn-example">(<span class="hl-fn">&gt;=</span> <span class="hl-num">5</span> <span class="hl-num">5</span>)  <span class="hl-comment">; true</span></div>
       </div>
 
       <div class="fn-card">
         <div class="fn-card-header">
-          <span class="fn-name">(within x lo hi)</span>
-          <span class="fn-type">atomic</span>
+          <span class="fn-name">(within vec [lo hi])</span>
         </div>
-        <div class="fn-desc">Check if value is within a range (inclusive).</div>
-        <div class="fn-example">(<span class="hl-fn">within</span> <span class="hl-num">5</span> <span class="hl-num">3</span> <span class="hl-num">7</span>)  <span class="hl-comment">; 1b</span><br>(<span class="hl-fn">within</span> [<span class="hl-num">1</span> <span class="hl-num">5</span> <span class="hl-num">9</span>] <span class="hl-num">3</span> <span class="hl-num">7</span>)  <span class="hl-comment">; [0b 1b 0b]</span></div>
+        <div class="fn-desc">Check if each element of a vector is within a range (inclusive). The second argument is a 2-element vector <code>[lo hi]</code>.</div>
+        <div class="fn-example">(<span class="hl-fn">within</span> [<span class="hl-num">1</span> <span class="hl-num">5</span> <span class="hl-num">9</span>] [<span class="hl-num">3</span> <span class="hl-num">7</span>])  <span class="hl-comment">; [false true false]</span></div>
       </div>
 
       <!-- ============================================================ -->
@@ -294,7 +275,7 @@ <h2 id="logic">Logic</h2>
           <span class="fn-type">atomic</span>
         </div>
         <div class="fn-desc">Logical NOT. Flips boolean values.</div>
-        <div class="fn-example">(<span class="hl-fn">not</span> <span class="hl-bool">1b</span>)  <span class="hl-comment">; 0b</span><br>(<span class="hl-fn">not</span> [<span class="hl-bool">1b</span> <span class="hl-bool">0b</span> <span class="hl-bool">1b</span>])  <span class="hl-comment">; [0b 1b 0b]</span></div>
+        <div class="fn-example">(<span class="hl-fn">not</span> true)  <span class="hl-comment">; false</span><br>(<span class="hl-fn">not</span> [true false true])  <span class="hl-comment">; [false true false]</span></div>
       </div>
 
       <!-- ============================================================ -->
@@ -352,7 +333,7 @@ <h2 id="aggregation">Aggregation</h2>
           <span class="fn-type">aggregate</span>
         </div>
         <div class="fn-desc">Median value.</div>
-        <div class="fn-example">(<span class="hl-fn">med</span> [<span class="hl-num">1</span> <span class="hl-num">3</span> <span class="hl-num">5</span> <span class="hl-num">7</span> <span class="hl-num">9</span>])  <span class="hl-comment">; 5</span></div>
+        <div class="fn-example">(<span class="hl-fn">med</span> [<span class="hl-num">1</span> <span class="hl-num">3</span> <span class="hl-num">5</span> <span class="hl-num">7</span> <span class="hl-num">9</span>])  <span class="hl-comment">; 5.0</span></div>
       </div>
 
       <div class="fn-card">
@@ -465,18 +446,10 @@ <h2 id="generation">Generation</h2>
 
       <div class="fn-card">
         <div class="fn-card-header">
-          <span class="fn-name">(take n x)</span>
+          <span class="fn-name">(take x n)</span>
         </div>
         <div class="fn-desc">Take the first <code>n</code> elements from a vector, or repeat/cycle <code>x</code> to length <code>n</code>.</div>
-        <div class="fn-example">(<span class="hl-fn">take</span> <span class="hl-num">3</span> [<span class="hl-num">10</span> <span class="hl-num">20</span> <span class="hl-num">30</span> <span class="hl-num">40</span>])  <span class="hl-comment">; [10 20 30]</span><br>(<span class="hl-fn">take</span> [<span class="hl-str">A</span> <span class="hl-str">B</span>] <span class="hl-num">5</span>)  <span class="hl-comment">; [A B A B A]</span></div>
-      </div>
-
-      <div class="fn-card">
-        <div class="fn-card-header">
-          <span class="fn-name">(drop n x)</span>
-        </div>
-        <div class="fn-desc">Drop the first <code>n</code> elements from a vector.</div>
-        <div class="fn-example">(<span class="hl-fn">drop</span> <span class="hl-num">2</span> [<span class="hl-num">10</span> <span class="hl-num">20</span> <span class="hl-num">30</span> <span class="hl-num">40</span>])  <span class="hl-comment">; [30 40]</span></div>
+        <div class="fn-example">(<span class="hl-fn">take</span> [<span class="hl-num">10</span> <span class="hl-num">20</span> <span class="hl-num">30</span> <span class="hl-num">40</span>] <span class="hl-num">3</span>)  <span class="hl-comment">; [10 20 30]</span><br>(<span class="hl-fn">take</span> [<span class="hl-str">A</span> <span class="hl-str">B</span>] <span class="hl-num">5</span>)  <span class="hl-comment">; [A B A B A]</span></div>
       </div>
 
       <div class="fn-card">
@@ -492,7 +465,7 @@ <h2 id="generation">Generation</h2>
           <span class="fn-name">(where x)</span>
         </div>
         <div class="fn-desc">Return indices where the boolean vector is true.</div>
-        <div class="fn-example">(<span class="hl-fn">where</span> [<span class="hl-bool">0b</span> <span class="hl-bool">1b</span> <span class="hl-bool">0b</span> <span class="hl-bool">1b</span>])  <span class="hl-comment">; [1 3]</span><br>(<span class="hl-fn">where</span> (<span class="hl-fn">&gt;</span> [<span class="hl-num">10</span> <span class="hl-num">5</span> <span class="hl-num">20</span>] <span class="hl-num">8</span>))  <span class="hl-comment">; [0 2]</span></div>
+        <div class="fn-example">(<span class="hl-fn">where</span> [false true false true])  <span class="hl-comment">; [1 3]</span><br>(<span class="hl-fn">where</span> (<span class="hl-fn">&gt;</span> [<span class="hl-num">10</span> <span class="hl-num">5</span> <span class="hl-num">20</span>] <span class="hl-num">8</span>))  <span class="hl-comment">; [0 2]</span></div>
       </div>
 
       <div class="fn-card">
@@ -505,10 +478,10 @@ <h2 id="generation">Generation</h2>
 
       <div class="fn-card">
         <div class="fn-card-header">
-          <span class="fn-name">(xbar n x)</span>
+          <span class="fn-name">(xbar x n)</span>
         </div>
         <div class="fn-desc">Round each element down to the nearest multiple of <code>n</code> (bucketing).</div>
-        <div class="fn-example">(<span class="hl-fn">xbar</span> <span class="hl-num">5</span> [<span class="hl-num">3</span> <span class="hl-num">7</span> <span class="hl-num">12</span> <span class="hl-num">18</span>])  <span class="hl-comment">; [0 5 10 15]</span></div>
+        <div class="fn-example">(<span class="hl-fn">xbar</span> [<span class="hl-num">3</span> <span class="hl-num">7</span> <span class="hl-num">12</span> <span class="hl-num">18</span>] <span class="hl-num">5</span>)  <span class="hl-comment">; [0 5 10 15]</span></div>
       </div>
 
       <!-- ============================================================ -->
@@ -541,18 +514,18 @@ <h2 id="higher-order">Higher-order Functions</h2>
 
       <div class="fn-card">
         <div class="fn-card-header">
-          <span class="fn-name">(apply f args)</span>
+          <span class="fn-name">(apply f ...args)</span>
         </div>
-        <div class="fn-desc">Apply function <code>f</code> with a list of arguments.</div>
-        <div class="fn-example">(<span class="hl-fn">apply</span> <span class="hl-fn">+</span> [<span class="hl-num">1</span> <span class="hl-num">2</span>])  <span class="hl-comment">; 3</span></div>
+        <div class="fn-desc">Apply function <code>f</code> to the given arguments.</div>
+        <div class="fn-example">(<span class="hl-fn">apply</span> <span class="hl-fn">+</span> <span class="hl-num">1</span> <span class="hl-num">2</span>)  <span class="hl-comment">; 3</span></div>
       </div>
 
       <div class="fn-card">
         <div class="fn-card-header">
-          <span class="fn-name">(filter f x)</span>
+          <span class="fn-name">(filter vec mask)</span>
         </div>
-        <div class="fn-desc">Keep elements of <code>x</code> where <code>f</code> returns true.</div>
-        <div class="fn-example">(<span class="hl-fn">filter</span> (<span class="hl-kw">fn</span> [x] (<span class="hl-fn">&gt;</span> x <span class="hl-num">2</span>)) [<span class="hl-num">1</span> <span class="hl-num">2</span> <span class="hl-num">3</span> <span class="hl-num">4</span>])  <span class="hl-comment">; [3 4]</span></div>
+        <div class="fn-desc">Keep elements of <code>vec</code> where the boolean <code>mask</code> is true.</div>
+        <div class="fn-example">(<span class="hl-fn">filter</span> [<span class="hl-num">1</span> <span class="hl-num">2</span> <span class="hl-num">3</span> <span class="hl-num">4</span>] (<span class="hl-fn">&gt;</span> [<span class="hl-num">1</span> <span class="hl-num">2</span> <span class="hl-num">3</span> <span class="hl-num">4</span>] <span class="hl-num">2</span>))  <span class="hl-comment">; [3 4]</span></div>
       </div>
 
       <div class="fn-card">
@@ -575,7 +548,7 @@ <h2 id="reference">Quick Reference Table</h2>
         <tbody>
           <tr>
             <td><strong>Arithmetic</strong></td>
-            <td><code>+</code> <code>-</code> <code>*</code> <code>/</code> <code>%</code> <code>neg</code> <code>abs</code> <code>sqrt</code> <code>round</code> <code>floor</code> <code>ceil</code></td>
+            <td><code>+</code> <code>-</code> <code>*</code> <code>/</code> <code>%</code> <code>neg</code> <code>round</code> <code>floor</code> <code>ceil</code></td>
           </tr>
           <tr>
             <td><strong>Comparison</strong></td>
@@ -595,7 +568,7 @@ <h2 id="reference">Quick Reference Table</h2>
           </tr>
           <tr>
             <td><strong>Generation</strong></td>
-            <td><code>til</code> <code>take</code> <code>drop</code> <code>reverse</code> <code>where</code> <code>find</code> <code>xbar</code></td>
+            <td><code>til</code> <code>take</code> <code>reverse</code> <code>where</code> <code>find</code> <code>xbar</code></td>
           </tr>
           <tr>
             <td><strong>Higher-order</strong></td>