Optimizing compilers may enable
strict aliasing.
For a wide variety of existing projects, strict aliasing provides additional optimization.
For some projects, such as
MUMPS,
memory leaks have been observed that are resolved by disabling strict aliasing using GCC flag “-fno-strict-aliasing”.
Compilers with ability to switch on / off strict aliasing include:
Zstd is an open file compression
standard.
Zstd has become widely used and is incorporated in the
Linux kernel
and GCC.
We use Zstd for data archiving particularly for large files where size and speed are a concern.
CMake supports Zstd compression throughout, including
file(ARCHIVE_CREATE)
and
file(ARCHIVE_EXTRACT).
Zstd is
vendored
into CMake, so there is no need to worry about system libraries for Zstd.
file(ARCHIVE_CREATE ... WORKING_DIRECTORY ...) is necessary to avoid system-specific relative path issues.
The Wouxun KG-S72C is a modern CB radio with AM and FM capabilities, which are recommended for anyone buying a new CB radio.
The KG-S72C has CTCSS and DCS coded squelch, which allows hearing only parties with the same subaudible code.
Only a few other models of CB radio have this capability, so most users might only occasionally use coded squelch.
An important point to note is that no one sells the KG-S72C factory antenna replacement, so be very careful not to lose or damage the factory antenna.
Since the KG-S72C receives an SMA female antenna (the radio has SMA female connector), using long replacement antennas are mechanically fragile and could break the antenna jack.
The sound quality on receive and transmit is good, especially in FM mode as for most AM / FM CB radios.
Lack of RF gain control, which is a fundamental requirement for any CB radio to make listening tolerable in AM mode. Using the KG-S72C as a mobile radio with an appropriate SMA adapter to the mobile antenna coax is OK, but the lack of RF gain control can be fatiguing and is the second con.
The squelch mode seems to be noise squelch only, which can be frustrating as it closes intermittently on loud AM modulation. It would benefit from a signal strength squelch as traditional CB radios use.
tl;dr: When connected to a captive portal, try visiting
http://neverssl.com
to trigger the portal.
Public WiFi often has
captive portal
login.
Portals may coerce users to accept terms and conditions and absolution of liability before accessing the Internet.
The portals may be worked around by DNS tunneling, MAC spoofing, etc.
Many users just tolerate the portals.
Web browsers may try to trigger captive portals by checking servers, in case the OS hasn’t already triggered the captive portal.
Sometimes captive portals aren’t triggered.
HSTS
blocks HTTP captive portal redirects.
Try visiting a deliberately non-HTTPS portal-triggering site like http://neverssl.com
Devices on networks that block the platform’s automatic network checking may indicate like:
Connected, no Internet
If there’s not a captive sign-in webpage, the network connection may still work to non-Google sites.
The Cobra 19 Ultra 6 appears to be a relabeled
AnyTone Smart II.
While previous Cobra 19 models had significant features missing, the Cobra 19 Ultra 6 has the necessary features to be a good choice in entry-level CB radio.
From practical in-vehicle use, the speaker is adequately loud.
Both AM and FM mode work well on transmit and receive.
There is no “dual watch” channel capability, but this may not be a requirement for many users.
RF Gain is essential on any CB radio and the RF gain adjustment range of the Cobra 19 Ultra 6 is good.
Typically RF gain between 24 and 39 is useful.
The radio appears to use audio compandoring, which helps improve apparent audio SNR.
The radio has a traditional signal squelch as well as “auto” noise squelch.
The general problem with noise squelch across CB radios is that overmodulated AM signals can close the squelch regardless of how strong the signal is.
Setting the RF Gain and Squelch on an AM CB radio is best done by opening the squelch – static is heard.
Then set the RF Gain so that faint static and/or skip signals are heard.
Then set the signal squelch just closed.
On firmware version 1.1, entering scan mode is different than the manual states.
To enter channel scan, press and hold the microphone “up” or “down” button until the radio goes once through all 40 channels, then the radio beeps and release the button.
The radio then scans all 40 channels repeatedly.
Unfortunately, there does not appear to be a way to skip channels in scan mode.
This means the radio will often stop on channels 6, 11, etc. with high power stations that may not be what the user wants to listen to.
In Matlab,
fitsread
is used to read specific frame(s) from a FITS file.
Read frames one at a time from a large multi-frame FITS file in MATLAB.
This avoids overwhelming RAM or taking an excessive time to load just one or a few image frames from a FITS file.
Example: sequentially read and plot each frame of a 4096-frame FITS file, with each frame being 256 x 256 pixels.
for i = 1:4096 currFrame = fitsread('myFile.fits', PixelRegion={[1256],[1256],i});imagesc(currFrame)pause(0.05)end
GNU Octave FITS reading is done with the
cfitsio
package using a
similar API.
The no-cost
AMD AOCC compiler
is tuned for AMD CPUs, akin to how Intel oneAPI is tuned for Intel CPUs.
For a RHEL-based Linux, install the downloaded “.rpm” file like:
The
AOCL libraries
provide accelerated math functions for AMD CPUs for several popular libraries for use in C, C++, or Fortran.
AOCL is compatible with AOCC and other compilers as listed in the AOCL downloads.
5G wireless network providers across the United States and elsewhere are turning on 5G standalone mode (SA), that can enable significantly more data bandwidth and lower connection latency.
Some phones, even recent phones, are not properly capable of supporting 5G SA even though they work fine in 5G NSA (non-standalone mode) that operates like 4G LTE.
Recent Android releases and carrier updates have disabled 5G SA for certain phones that previously had 5G SA enabled due to data connectivity problems when the carrier enabled 5G SA.
A symptom of lost data connectivity, possibly due to 5G SA incompatibility, is the phone signal showing 5G signal bars with an exclamation point.
What may possibly but not always help is to turn off 5G in the phone network settings by setting “Preferred network type” to “LTE” or similar instead of “5G”.
This may force the phone to use 4G LTE instead of 5G, which may work better for data connectivity.
However this does not always help.
If a newer phone on the same network carrier works fine with 5G SA, then the phone with data connectivity problems may need a software update or carrier update to fix the problem, or simply a newer phone may be needed.
The Network Cell Info app can show the network type and signal strength, and may help diagnose the problem.